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Volume 18 Winter 2001

Corals in Bali Barat National Park largely escaped bleaching in 1998.

9th InternationalCoral Reef SymposiumReport

The ConscientiousReef Aquarist:Blue-Green Algae (Cyanobacteria) inMarine Aquariaby Robert Fenner

Problems associated with blue-green algaeaccount for a large number of requests for helpthat I receive over the Internet. I suspect thatblue-green algae problems account for more lossof captive life than any other cause, exceptingdeaths resulting from ammonia problems. Blue-green algae are simple life forms, and easilydefeated in aquaria. A discussion follows thatdescribes what they are, why they are undesirablein an aquarium, and how to get rid of them.

ClassificationBlue-green algae are more properly known as

Cyanobacteria. Cyanobacteria and true bacteriaare classified in the kingdom Monera. True algaeare actually in the kingdom Protista, along withsimilar life forms. Although Cyanobacteria are notreally algae, the distinction is a technical one, andmany people continue to call them blue-greenalgae. Many species of blue-green algae that areencountered by aquarists are microscopic, butsome forms resemble green filamentous algae.Colonies generally appear to be blue-black orreddish slimes, smears, or filamentous threads.

EnvironmentBlue-green algae can be introduced into an

aquarium in newly-added live rock, in waterwith livestock additions, in food, and even asspores entering by means of the air supply. Ingeneral, they are more tolerant of fluctuationsin pH, temperature, and specific gravity thandesired aquarium species. The best defenseagainst too much blue-green algae is thepromotion of the stable conditions that favorgrowth of true algae. Maintain good waterquality by cleaning filters and making regularwater changes, thus eliminating as much aspossible organic and inorganic nutrients. Thisshould help to keep the nitrate level below 10parts per million and the phosphate level below0.5 parts per million. Of course, overfeeding is aprime source of the organic compounds thatfuel blue-green algae. Be particularly careful touse only a minimum of liquid invertebrate andgelatine-based frozen foods.

LightingThe second most important consideration

for algae in an aquarium, after water quality, islighting. Providing light that is adequate forgrowth of beneficial algae is the best way todiscourage the growth of blue-green algae. A

by Tom Frakes and Rand Kollman

This past fall we had the opportunity toattend the 9th International Coral ReefSymposium held on the island of Bali, Indonesia.Every four years this conference brings togetherreef scientists, environmentalists, andgovernmental representatives from around theworld to discuss the state of the world’s coralreefs. For five days, each morning and afternoonsession was opened with a one hour plenary talk,followed by several hours of scientific presenta-tions spread among fourteen separate rooms.These twenty minute presentations coveredtopics ranging from coral physiology to reefecology to the social and political effects of reefmanagement practices. There were almost 2000participants. Choosing and finding presentationseach day was quite a job. We would like tohighlight a few of the sessions we attended thatmay be of interest to marine aquarists.

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Reef DegradationNumerous papers concerned with reef

degradation discussed localized reef destructionand the effects of temperature and pollution. Onesession, led by Dr. E. A. Shinn, considered theeffects of African dust on Caribbean reefs. Stormsin African deserts result in dust carried by thewind across the Atlantic to the Caribbean,northern South America, and the United States.These clouds of dust contain iron, nitrogen, andphosphate which rain down on the reefs,fertilizing algae and stimulating algal blooms. Inrecent years the African deserts have increased insize, resulting in an increase in the amount ofdust, now estimated to be as much as a billiontons a year. In a recent study that compared airquality in 79 U.S. national parks, the St. JohnsIsland National Park in the U.S. Virgin Islands hadone of the highest counts of particulates in the air.

Another presentation concerned the risk toCaribbean reefs from increased African use offertilizers and pesticides. A common terrestrialfungus that causes aspergillosis in two sea fanswas isolated from the African dust by J. Weir andhis associates. It was also suggested that the

PUBLICATION INFORMATIONSeaScope® was created to present short, informativearticles of interest to marine aquarists. Topics mayinclude water chemistry, nutrition, mariculture, systemdesign, ecology, behavior, and fish health. Articlecontributions are welcomed. They should deal withpertinent topics and are subject to editorial reviews thatin our opinion are necessary. Payments will be made atexisting rates and will cover all author's rights to thematerial submitted.

SeaScope® is published quarterly for free distributionthrough local aquarium dealers. Dealers not receivingcopies of SeaScope® for distribution to theircustomers should call Aquarium Systems, Inc. to beadded to the mailing list. Telephone: 1-800-822-1100.Aquarists interested in receiving copies directly shouldsend their name and address, along with $2.00 ($4.00foreign countries) for postage and handling (four issues)to SeaScope®, Aquarium Systems, Inc., 8141 TylerBlvd., Mentor, OH 44060. Address comments,questions, and suggestions to Thomas A. Frakes, Editor.

Internet: www.aquariumsystems.com or E-Mail: [email protected]

Refinishing a WorkingPlexiglass ReefAquariumby LeRoy Headlee

At Geothermal Aquaculture ResearchFoundation we maintain about forty separatesystems for the study of ornamental coralproduction. Each October we hold aninternational Reef Farming Seminar, and inSeptember last year we knew we had to do a lotof cleaning before the seminar. I have a four yearold 150 gallon plexiglass reef aquarium in myoffice. Several days before the seminar a housepainter decided to pitch in and help by cleaningthe tank. The internal glass cleaning magnet fellinto the gravel and trapped a sharp piece of sand.When he had finished helping, there was scarcelya section of the plexiglass that was not scratched.

At this point, it was hard to remember thatthe painter was just trying to help. That reefcontains over a hundred types of coral, and therewas no way to tear down the system and remakeit before the seminar. I needed to find a way topolish the front inside surface of the aquariumwhile the animals were in the aquarium, onlyinches from the front surface.

I spent over a decade working as an antiquerefinisher to pay my way through college, and Iunderstand how to polish surfaces. I hadexperience polishing the outside of the coralfarming units with wet and dry sandpaper and aliquid plastic polish, but I couldn’t use the polishinside the aquarium because it would be toxic tothe animals. I decided to use a pair of Twister ®

magnetic aquarium cleaners with wet and drysandpaper. The magnets were perfect for this jobbecause they are thin and very strong. Sandpaperis graded by a number system. The larger thenumber the finer the grit. I started with 400 gradepaper and ended with 2500 grade. Although astandard paint store will carry 400 and 600grades, finding the higher grades may be aproblem. My sister referred me to a hot rodbody shop, where I was able to purchase a half

sheet of 1200, 1500, 2000, and 2500 grade forfifty cents each. I used Nova Light #2 andHeavy #3 Acrylic Scratch Polishes on theoutside surface to polish the plexiglass andlubricate the magnet. They are available fromNovus Company, 800 548-6872, or from aplastics wholesaler.

ProcedureThe materials you will need include one

pair of Twister® aquarium magnets, one tube ofthick gel super glue, a roll of soft paper towels,one bottle each of Nova Acrylic Heavy ScratchPolish and Light Scratch Polish, and one pieceeach of 3M Imperial Wet or Dry sandpapergrade 400, 600, 1200, 1500, 2000, and 2500.Use the following procedure on a small,inconspicuous test section of your aquarium togain confidence and technique before polishingthe entire front panel.

If you can dedicate the pair of magnets to thisproject, attach the sandpaper to the insidemagnet using four large drops of super glue. Ifyou’re going to use the magnets later for cleaningaquariums, attach the first sheet of sandpaperwith two strong rubber bands. Begin removingthe scratch by using 400 grade paper attached tothe inside magnet and squeezing a two inch longline of heavy scratch polish on the felt pad of theoutside magnet for lubrication. It is veryimportant to remember to move the magnets

only in a horizontal, back-and-forth direction.Make one stroke the length of the aquarium andthen reverse. The first few strokes will allow youto judge the best speed to use. If the innermagnet falls to the bottom of the aquarium besure to remove any sand or gravel beforecontinuing. Remove the inner magnet every fewminutes and wash the sandpaper with fresh waterand clean paper towels. This will remove anygummy build up on the sandpaper.

Add new sheets of 400 grade sand paper untilthe entire inner surface is sanded and themajority of the scratches removed. To add a newsheet on top of the old one, place four drops ofsuper glue on the old sheet and press the newone in place. When it becomes clogged, pull it offthe old sheet and replace it. The 400 grade paperwill do most of the work and is the leastexpensive grade. Move on to the 600 gradepaper, still using the heavy polish. After the 600grade paper, wash the outside magnet in tapwater and change to the fine scratch removingpolish. When you have finished with the 2000grade paper you will see that the inner glass ispolished. The final polish, with 2500 gradepaper, is necessary if you plan to photographthe reef. Sand lightly in a random circularpattern. Other-wise, the light will refract fromthe parallel grooves in the polished surface.Such refraction is not noticeable to the eye,but is obvious in a photo.

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massive die-off in 1983 of the long spined seaurchin Diadema might have been due to a dustborne factor.

AlgaeDiane Littler and Mark Littler, authors of the

recently released book Caribbean Reef Plants, leda session on algae. Their paper and one by Smith,Smith, and Hunter support the RelativeDominance Model originally proposed in 1984 byLittler and Littler. It predicts the dominance ofcoral, coralline algae, turf algae, or fleshy algae onreefs based on the balance of nutrients andgrazing. One extreme of low nutrients and highgrazing would result in coral dominance. Theother extreme is high nutrients and reducedgrazing that would result in an overgrowth offleshy algae. Possibilities between these twoextremes would include elevated nutrients withhigh grazing, resulting in coralline algaedominance, and low nutrients with reducedgrazing, resulting in turf algae dominance. Thismodel can be considered both for coral reefaquariums, where we all battle algae, and for themanagement of ornamental fisheries, wheregrazers are removed from reefs.

Collection StandardsSeveral sessions were devoted to the topic of

uniform collection standards for both theornamental trade and the live food fish trade. PaulHolthus, the executive director of the MarineAquarium Council, participated in discussionsrelating to developing certification standards forthe collection and handling of marineornamentals. He has agreed to discuss thisprogram in SeaScope at a later date. Severalpapers described efforts to monitor the coraltrade and to standardize reporting methods toprovide better data for use in makingmanagement decisions. In the past, coral importswere reported by weight or by piece count, andoften included live coral, coral skeletons, coralsand, and occasionally live rock. The data camefrom import permits. In the future each categorywill be reported separately to provide moremeaningful information.

CultureCulture of coral and reef organisms was the

subject of some sessions. Culture programs aredesigned for restocking damaged areas orsupplying the aquarium trade. Walt Smith

9th International Coral ReefSymposium Report

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described his efforts in Fiji to cultivate coral andlive rock to supplement wild harvests for the pettrade. C. V. Dinar, an exporter of marine fish andcoral, has set up a culture project on Bali to rearcorals and clams. Several other projects aredesigned to culture coral for restoration ofdamaged or declining reefs. Of particular interestis a project in Cebu, Philippines that restoresreefs in that area. This community based projectcould expand to other areas, and could possiblysupply the pet trade in future if laws werechanged to permit export of cultured coral.

An interesting approach to reef restoration isthe use of electricity to accelerate formation ofartificial reef structures. Tom Goreau, WolfHibertz, and others term the process electrolyticMineral Accretion, and report that such artificialstructures in the Maldives have better coralgrowth and more fish than natural control reefs.A demonstration site was set up on Baliconsisting of a titanium wire mesh anode and acathode frame made of steel bars. A low voltagecurrent is connected to the two parts, producinghydroxide ions on the cathode, raising the pH onthe surface and accelerating the precipitation ofcalcium carbonate onto the steel frame an inchthick or more. Corals attached to this structuregrow faster than nearby corals without theelectrical current. It has not yet been establishedwhether this patented process has an applicationfor coral culture in tanks.

Destructive Fishing Practices Several papers dealt with destructive fishing

practices. Ferdinand Cruz of the InternationalMarinelife Alliance described the plight of poorfisherfolk trying to feed their families whiletrapped between an expanding population anddeclining fisheries. The use of cyanide and itseffects were discussed, but mostly in the contextof the live fish food trade destined for Hong

Kong. Damage does still threaten the reefs, evenin areas where non-destructive hook and linefishing occurs, if larger food fish are over-fished tonearly the point of local extinction.

Climate ChangeWhole sessions were devoted to the effects

of global climate change and increased carbondioxide levels on corals in the next century. Oneconclusion was that a higher atmospheric carbondioxide level results not only in greenhouse effectelevated temperatures, but also in lower pHlevels, reducing the calcification rate for corals.Thus corals are doubly at risk. A paper by B.Opdyke and Bob Buddemeier reviewedtemperature, carbon dioxide levels, and coral reefdevelopment over the last 70 million years. Earlyin this period sea water was warmer with a lowerpH because of higher carbon dioxide levels.Corals existed, but were not the main reefbuilders. Gradually, temperature and carbondioxide levels dropped, after which time coralsflourished and the ratio of magnesium to calciumin sea water more than doubled. What willhappen as we move back toward these conditionsagain but with lower calcium levels?

Urchin RecoveryOf major interest was the die-off of the long

spined Caribbean sea urchin Diadema antillarium in1983. As mentioned before, some believe thisevent was due to a higher than normal influx ofAfrican dust. It has been proposed that their slowrecovery has been a cause of coral loss on theseCaribbean reefs. J. Woodley and others reportedthat Diadema are slow to move into reefs withdense fleshy algal growths. However, on a reefwhere a bloom of the short spined urchinTripneustes esculentus grazed the fleshy algae downto a short turf, the Diadema population recoveredand maintained the reef, allowing corals to return.

Dead table coral from the 1998 bleaching event,Permuteran, Bali.

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Coral and clam farm on the north coast of Bali, set up by the export company C. V. Dinar.

Electrolytic Mineral Accretion reef near Pemuteran, Bali. Titanium wire anode (left) and steel re-bar frameworkcathode with limestone coating and corals (right).

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good rule of thumb is to provide 2 to 5 watts pergallon of white daylight, avoiding yellowish, oldbulbs. Standard, high output, very high output,compact fluorescent, and metal halide bulbs haveall been employed with good success.

FiltrationAny type of filtration, whether chemical,

physical, or biological, that removes excessnutrients such as nitrates and phosphates, isdesirable. Limiting excess nutrients will benefittrue algae, which is generally in competition withblue-green algae.

Aeration and Water CirculationBlue-green algae thrive in areas that are

poorly aerated and have low water circulation.Using power heads, small submersible pumps, andmechanical aerators, as well as directing thedischarge from outside filters and pumps, are allgood ways to increase circulation and aeration.

The Conscientious Reef Aquarist: Blue-Green Algae (Cyanobacteria) in MarineAquaria

Control of Blue-Green AlgaeEven when proper precautions are employed,

aquarists sometimes still encounter blue-greenalgae in their aquariums. Following are severalmethods to control this problem.1. Manual Removal - Gently wiping the sides of

the aquarium and regularly removing algaefrom gravel and other surfaces can do a lot tolessen the problem.

2. Siphoning - Siphoning works directly toremove the algae, and also seems to trigger akind of chemical self-destruction. A smalldiameter rigid tube attached to a siphon hoseis normally sufficient.


3. Limiting Food - It is important to limit nitratesand phosphates. Do not overstock or over-feed fish and invertebrates. Also be wary oftoo many chemical supplements, and ofnitrates or phosphates that may be present intap water or synthetic sea salt.

4. Increasing Filtration - Improving theefficiency of protein skimmers andpreserving and increasing redox potentialwill benefit desirable algae. Chemicalfiltration can remove chemical nutrientsthat may be present.

5. Controlling Biologically - Except for a fewhermit crab species, there are no animals thatgraze on blue-green algae. Instead, theproliferation of blue-green algae can becontrolled by competing life forms, such asmacro algae, live rock, and some corals,gorgonians, and anemones, which utilizeavailable light and nutrients. These organismsproduce certain chemicals that also combatthe spread of blue-green algae.

AntibioticsNumerous products have been promoted as

chemical controls for blue-green algae. Theseinclude various forms of erythromycin, copper,sugar, and even pepper sauce. They all should beavoided, although some of them may actuallywork. Once the blue-green algae die, theremnants frequently poison the aquarium. Also,unless conditions in the aquarium are changed,the algae will quickly rebound, and may evendevelop into resistant strains.

Suggested Reading

Please contact Aquarium Systems, Inc. at 800 822-1100 for a list ofreferences related to this article.

Book Review:

The MarineAquarists’Quiz Book by Martin and Barbara Moe

Reviewed by Rand Kollman

The hobbyist who reads The MarineAquarists’ Quiz Book by Martin and Barbara Moewill be both educated and entertained. Throughthe format of multiple choice questions, theauthors present detailed information of greatpractical value on a wide range of aquarium-related topics. The book is organized into fivesections of eighty questions, with theaccompanying answers on the back of each pageof questions.

The first section, titled Marine Fish, deals withfish identification and biology. The second sectiondeals with Marine Invertebrates in a similarmanner. The third section, Marine Aquaristics,delivers practical information on basic andadvanced aquarium theory, with a new look atterminology, equipment, and techniques. Thefourth section, Reef and Sea, discusses marineaquariums in the broader context of the captiveand natural environment, the oceans and seas,and their inhabitants. The final section, MarineMiscellany, covers a wide assortment of marinetopics, including history, people, public aquariums,hobbyist associations, and additional informationabout reef and sea creatures.

The Marine Aquarists’ Quiz Book is wellwritten and easy to read. It is an excellentreference book for the beginning, intermediate,and advanced hobbyist.

Upcoming Events

Western Marine Conference - 2001Marine Aquaria: Challenges for Today andTomorrowApril 22 - 24, 2001, Monterey, CaliforniaHosted by SEABayFor information visit: www.seabay.orgor contact Rod Leong, (510) 538-9495e-mail: [email protected]

Marine Aquarium Conference of North AmericaMACNA XIII: “The Living Seas”NOTE: Date change from previous issure ofSeaScope: August 17 - 19, 2001, Baltimore, MarylandHosted by MASNA and The Chesapeake MarineAquaria Society. Visit: www.cmas-md.org or www.masna.org/M13

2nd International Conference on MarineOrnamentalsNovember 27 - December 1, 2001, Walt DisneyWorld Resort, Lake Buena Vista, FloridaFor more information visit:www.ifas.ufl.edu/~conferweb/MOor call: (352) 392-5930

Plenary TalksTwo plenary talks were particularly

interesting. Dr. J. Veron spoke about reticulateevolution; that is, over time, corals divide intoseparate species and then recombine underdifferent conditions as time passes. Dr. Veronalso introduced his new three volume Corals ofthe World, which is now available. Dr. DavidBellwood explained his use of ecomorphologyto compare reefs around the world. Reefinhabitants are characterized by function oforganisms, rather than species. In other words,species may differ from reef to reef, but someorganisms must still perform various functionsfor the system to be successful.

It is impossible to summarize all the topicsdiscussed during the five day symposium. Thesehighlights of the nearly 1500 papers presented aremeant to pique the interest of the aquarist andfuture reef biologist. We will continue to look forarticles from this symposium list that may be ofinterest to marine aquarists.

9th International Coral ReefSymposium Report


Top: Scytonema blue-green algae. Bottom: Zygnemagreen algae.

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ISSN 1045-3520FREE

Volume 18 Spring 2001

Inimicus didactylus

Speak of the Devil:Fish in the genus Inimicusby Scott Michael

Caulerpa Ban inCaliforniaby Thomas Frakes

The possession of all species of Caulerpa algaemay soon be illegal in California, if the recentlyintroduced Assembly Bill #1334 is passed intolaw. This bill comes after years of headlines about“Killer Algae” from the Mediterranean region.Last year two patches of Caulerpa taxifolia, whichthe press likes to call “Killer Algae,” were foundin southern California.

Before continuing, I must emphasize that therelease of any non-native organism into theenvironment is illegal in California and most otherstates. Hobbyists should never dischargeaquarium wastes, water, decorations, ororganisms into the environment. Proper disposalrequires treatment of water by a wastewatertreatment facility, and all other wastes should goto a solid waste facility. This is true for bothfreshwater and marine organisms. Also, the saleand importation of the Mediterranean strain ofCaulerpa taxifolia has been illegal in the UnitedStates and in many European countries for severalyears since it has been listed as a nuisance species.

The Caulerpa strain that was found inCalifornia seems to be the same one that wasonce popular in European public aquariums in theearly 1980’s. It has spread to many areas of theMediterranean since it was first reported offMonaco in 1984. In the last decade manynewspapers, magazines, and even a book havepredicted dire consequences if this “invasive”species spreads. The predictions included claimsthat the Caulerpa would overgrow everything inits path, destroying fisheries, seagrass beds, andnatural ecosystems throughout the region.Recent scientific studies now show that, althoughCaulerpa has spread to numerous areas, thefisheries have not been destroyed, and the claimthat it blanketed more than 10,000 acresexaggerates the truth by a factor of 100. Of theareas Caulerpa has covered, 80% were putrid mudbottoms that would not sustain native seagrass ormany other organisms. In the next few years wewill see more data that show this has not beenthe ecological disaster that was predicted.

Although it is true that this species is notnative to California, Caulerpa taxifolia is foundnearly world wide in the tropics. It existsnaturally on both sides of the Atlantic and intothe Gulf of Mexico, as well as from the Red Seaacross the Indian Ocean and over most of thePacific from Japan and Hawaii to Australia. It isnot native to California waters because they aretoo cold. In fact, many botanists were surprised

The members of the genus Inimicus arecommonly referred to by the colorful commonnames walkmen, sea goblins, bearded ghouls,Chinese ghouls, demon stingers, and devilfish.Scientists tell us that the eight species in thisgenus belong to the family Scorpaenidae and thesubfamily Choridactylinae, although some placethis subfamily in its own family Synanceiidae withthe stonefish. All Inimicus members have two freepectoral rays which they use to pull themselvesacross the sea floor. They also have a crocodile-like flattened snout with eyes situated high on thehead. Of course, these fish are most famous, orinfamous, for their highly venomous spines,especially the long, needle-like dorsal spines. Eachone of the fifteen to eighteen spines, dependingon species, is supplied with toxin by an associatedvenom gland.

In addition to its venomous spines, thedevilfish’s next defense against predators is itscryptic coloration. Most of the time the colorshelp it blend into its surroundings, especiallywhen it is partially buried in the sand or mud.However, when disturbed the devilfish will erect

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its dorsal spines and throw its pectoral finsforward, exposing the bright or contrastingcolors on the inner surfaces of the fins, as well asfanning out the colorful caudal fin. If these colorswere visible when the fish is in repose the fishwould be conspicuous, and perhaps this wouldinterfere with obtaining food. Sudden exposure ofthese colorful markings may serve to warn largerfish that it is not good to eat, and to startlewould-be predators.

Devilfish are limited in distribution to thecentral and western Pacific and the IndianOceans. One species is sometimes seen in coastalhabitats in the Red Sea. Several species arecommonly encountered by divers in the westernPacific. Inimicus species are found on sand andmud bottoms, adjacent to reefs, in sea grassmeadows, and in estuaries.

Painful EncounterDevilfish lead pretty lazy lives. During the day

they are often partially buried in the substratewith only the dorsal fin and top of the headexposed. They are almost impossible to detect.Divers often become aware of a buried individualonly after placing an appendage, usually a hand,near one, causing the fish to erupt from thebottom. On my last trip to Inimicus infested seas, I

A System forLaboratory orCommercial Culture ofGobiid Fishesby Todd Gardner and James L. Van Tassel

Biology Department, Hofstra University, Hempstead, New York

The Gobiidae, comprised of approximately2000 species, is the largest family of marine fishes(Robins et al., 1987), and is probably one of thelargest vertebrate families. Gobiids are animportant component of the aquarium fishindustry throughout the world (Burgess et al.,1988) and are used as food in some cultures(Fishbase, 2000). Despite numerousinvestigations, information regarding egg andlarval development remains relatively scarce(Moser, 1983). One problem with many early lifehistory studies on gobies and other marine fishesis that larval specimens have historically beenobtained from the wild in plankton samples(Moser, 1983; Van Tassel, 1998). Larval fishcollected in this manner are often physicallydamaged and the exact age can be impossible todetermine. The use of aquaculture techniques tospawn and raise marine fish species in thelaboratory allows us to look at eggs and larvaeevery day of their development, and at thecourtship and spawning behavior of matureadults. Furthermore, information gathered fromlaboratory culture investigations can be a valuableresource for people interested in developingaquaculture as an environmentally soundalternative to the exploitation of wild fisheries.

At Hofstra University Marine Laboratory inHempstead, New York we have constructedsystems and initiated a protocol for captivecultivation of gobiids and other small marine fishspecies. Presently we have two broodstocksystems in place capable of holding a total of 36spawning pairs of fish. A 300 gallon larval rearingsystem of cylindrical polyethylene tanks is underconstruction, but larvae are currently raised in 10gallon aquaria. The rotifer Brachionus plicatilis isused as a first food, followed by Artemia nauplii,and eventually commercially prepared dry foods.The marine alga Isochrysis galbana is used as awater conditioner and food for the zooplankton.

BroodstockTwo systems, A and B, hold pairs of mature

fish. System A consists of seven 10 gallon aquariaand six 29 gallon aquaria. System B has five 10gallon aquaria and twelve 5 gallon aquaria. Thenumber of aquaria in each system wasdetermined by available space on the supportstructures that were scavenged for the project.The filtration for each system consists of an opencell foam prefilter, a 2100 cubic centimeter tricklefilter with plastic Bio-balls, and a 150 centimeter(cm) by 10 cm cylindrical acrylic protein skimmer.All components in each system are powered byan 1800 gallon per hour Mag-drive™ submersiblepump. All return lines and drain lines areconstructed of standard PVC pipe and fittings.Water flow to each tank is controlled by a 1/2inch PVC ball valve. A Lustar breeder box is ineach 10 gallon tank, allowing us to keep twospawning pairs in those tanks without the dangerof territorial aggression. The salinity of bothsystems is maintained at 30 parts per thousand(ppt) using Instant Ocean® synthetic sea salt.

Broodstock specimens were collected by theauthors in Puerto Rico, Florida, and New York,or obtained from retail aquarium shops.

The broodstock is fed three times a day,each time with a different food. The first food is afrozen gelatine based diet prepared with a blendof fresh seafood, vegetables, marine algae,Ziegler’s salmon starter, and a multi-vitaminsupplement. The second is a finely choppedmixture of clams, shrimp, squid, and capelin roe.The third is frozen, enriched Artemia.

A short length of 1/2 inch PVC pipe is placedon the bottom of each enclosure to serve as aspawning substratum. Eggs are deposited on theinside of the pipe by the female and fertilized bythe male. The male then guards the eggs untilhatching, which occurs in three to seven days,depending on species and temperature. Weremove two to five eggs each day to study theirdevelopment by microscopic examination andphotography. For larval rearing investigations wevisually inspect the eggs each day, but do notphysically disturb them until they are ready tohatch. Goby eggs are ready to hatch when theeyes become fully pigmented and the yolk sacsare no longer visible. Then we remove theentire pipe section from the aquarium andhold it under water in the larval rearing tankwhile gently pipetting water over the egg massto induce hatching.

Larval RearingIn preparation for hatching, a ten gallon larval

rearing tank is filled with synthetic sea water witha salinity of 30 ppt. The water is gently aerated by

means of a ceramic airstone. Then we add oneliter of Isochrysis and approximately 40,000rotifers, represented by 10 rotifers per milliliter(ml) of water. After the hatching we monitor therotifer concentration daily by removing 1 ml ofwater to a depression slide and counting theindividuals by means of the 40X lens of adissecting microscope. We maintain the rotiferconcentration at approximately ten per milliliter,and add one liter of Isochrysis daily.

About fifteen days after the hatching weintroduce Artemia salina nauplii to the diet. Afterfive to ten days of overlapping foods, the larvaereceive Artemia exclusively. All rotifers andArtemia are soaked in a commercially-preparedsuspension of highly unsaturated fatty acids(HUFA) for twelve to sixteen hours prior tofeeding. Once the rotifer diet has beencompletely replaced by Artemia, alga is no longeradded, and an air driven foam filter is placed inthe tank to help maintain good water quality.Also, a 50% water exchange is performed everythree to four days. Water is siphoned outthrough a section of flexible air tubing that has a500 micron Nitex® sleeve over the end to keeplarvae from being siphoned out. Replacementwater is siphoned into the tank from asuspended bucket.

Most of the gobiids we work with reachmetamorphosis about thirty days after hatching,although some species, such as Tigrigobiuspuncticulatum and Coryphopterus personatus cantake fifty to sixty days. We define metamorphosisas a significant increase in pigmentation, usuallycoupled with settlement from a pelagic to abenthic mode of existence. Around the time ofmetamorphosis we introduce dry food to the dietand use it exclusively within three weeks. At thispoint juveniles from various rearing tanks areconsolidated into twenty-nine gallon tanks insystem A. During the larval period two larvae areremoved per day from each rearing tank forphotography and observations of osteologicaldevelopment.

Plankton CultureThe microalga Isochrysis galbana is cultured in

an isolated room with fluorescent light banksaccording to the protocol outlined by Hoff andSnell (1987). Rotifers are cultured in ten gallonaquaria at a salinity of 25 ppt on a combination ofCulture HUFA from Salt Creek, Inc. andconcentrated Isochrysis paste from ReedAquaculture, Inc. Culture densities range from100 to 250 per milliliter. Artemia cysts aredecapsulated with household chlorine bleach,refrigerated in a saturated salt solution, andhatched as needed.



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Tigrigobius multifasciatum

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Tigrigobius macrodon (eggs)

actually rested my hand on one and was fortunatenot to have been jabbed by the spines. I waslucky, but some divers aren’t. There are anumber of reports of divers being stung by thesefish after touching them with a hand or knee.Photographers seem to be especially prone tothis, as they are very likely to rest on the bottom.The sting is very painful and can hurt for hours.Some victims have been known to feel pain fordays. Swelling of the injured limb is also common.If the sting is severe the victim could go intoshock and have difficulty breathing. If you arestung, seek medical attention immediately. WhileInimicus stings are rarely fatal, they could be.

I have noticed that in the wild these fish oftenbury themselves near small patches of debris orcoral heads scattered on sand slopes. They areattracted to these places for the same reasonphotographers are – such places are focal pointsfor fish and invertebrate activity. Because of this,make sure you are very careful when resting onthe sand near these oases of animal activity. (On arecent trip to Indonesia, underwaterphotographer Alan Ayling wore hockey kneepads over his wet suit to prevent accidentalstings.) It has been reported that at least onespecies of devilfish will attack photographers,although I find this hard to believe. I haveencountered hundreds of these fish, but have yetto be harried by one.

Stealthy PredatorThe more highly-adapted forms of Inimicus

have eyes that are set higher on the head and themouth is more turned up. These two featuresenable them to bury themselves deeper in thesand and still catch fish that swim past. Whenburied, the sea goblin will place its free pectoralrays in front of its body so that it can pull itselfforward quickly to capture passing prey. Thesefish feed mainly on crustaceans and small fish, andI have also seen them snap up swimmingpolychaete worms at night. They will either usean ambush strategy to capture their prey or willstalk their quarry by slowly moving towards it ontheir leg-like pectoral rays. Even as a devilfishmoves over the bottom, it may strike at any fishthat swims too close. Bruce Robinson, a friend ofmine, has footage in which a devilfish snaps up acardinalfish swimming past as the devilfish walksover the bottom.

I assume that, like stonefish and many otherscorpionfish, devilfish can shed their cuticle, theouter layer of skin. Some sedentary fish do this inorder to shed algae and encrusting organismsgrowing on the surface of their bodies.

Courtship or Aggression?On several occasions I have seen spiny

devilfish (Inimicus didactyla) engaging in what I havetentatively identified as courtship behavior. Ontwo occasions a smaller fish chased a largerconspecific across the sand. As the smaller fishmoved closer it displayed, flaring the pectoral finsand tail and parading around the larger fish.

On another occasion I was photographing aspiny devil when I accidentally disturbed anotherone, which emerged from the sand and rubble.The second individual was larger, with a broader

Speak of the Devil:Fish in the genus Inimicus


snout and a greatly distended abdomen,suggesting it might be a female ripe with eggs. Thepair moved slowly over the bottom, the smalleranimal moving alongside and cutting in front ofthe larger one. Occasionally the smaller fishdisplayed. The larger fish did not respond, butslowly lumbered forward in an apparent attemptto escape the possible suitor or aggressor.

Aquarium CareDevilfish are not for everyone, because most

of their time is spent in repose or under theaquarium substrate. Like a peculiar work of art,they are oddities that are appreciated most bythe collector of the unusual. Also, the fact thatthey are highly venomous means there is the riskof being stung. For this reason they should neverbe kept in a home where small children haveaccess to the tank. One beneficial aspect of theirsluggishness is that they can be kept in smalleraquaria without any ill-effects. You could easilykeep a devilfish in a 30 gallon aquarium. Youshould probably keep only one per tank toprevent aggression, unless the aquarium is over100 gallons with plenty of open bottom area.Two males of the same species could beespecially aggressive.

As far as aquascaping is concerned, you willneed at least two inches of fine substrate such asaragonite or fine coral sand on the aquariumbottom. If you have larger specimens the depthshould be increased so the fish can bury itselfcompletely. It is also a good idea to be sure theaquarium has a cover. These heavy-bodied fishdon’t look as though they would be proficientjumpers, but a friend of mine recently had onejump out of an open aquarium.

You can keep an Inimicus in a reef aquarium ifyou are not interested in housing shrimp or smallfish in the same tank. You will need to provideplenty of open bottom space to bury in and crawlover. This is a feature often in short supply in atank full of live rock. Remember that these fishlive on open sand slopes or sand flats adjacent tocoral reefs, not on the reef itself. Also remember,whether the tank is a reef tank or not, to bevigilant when working in the tank so you do nottouch the venomous spines accidentally.

Feeding and TankmatesLive food, such as ghost shrimp or small

feeder cardinalfish, is usually necessary to elicitthe feeding response from a devilfish.Occasionally a specimen will refuse even livefood, while another may be enticed into takingstrips of fresh fish from a feeding stick. Youshould avoid feeding a diet of only goldfish. Raw

goldfish flesh contains thiaminase, an enzyme thatcauses the breakdown of thiamine. A devilfishthat eats only goldfish may become thiaminedeficient, resulting in loss of appetite, clampedfins, and coordination problems. The best way toinsure good health is to feed a varied diet of freshand frozen seafoods.

Hepatic lipidosis, or fatty degeneration of theliver, has been reported in a closely related reefstonefish that was fed only fresh hake. Thiscondition can cause liver failure, leading tosuppression of the immune system,hemorrhaging, and anemia. This condition can beavoided by feeding as varied a diet as possible andby not overfeeding. I recommend feeding onlytwice a week.

Many aquarists believe that because devilfishand other scorpionfish are venomous other fishwill not bother them. This is far from the truth.Wobbegongs, morays, frogfish, and even otherscorpionfish will swallow these fish whole. Also,because these fish blend into the reef backgroundso well, they may be nipped and damaged byangelfish, triggerfish, and puffers as they feed onencrusting invertebrates.

Possible Devilfish ProblemsThe Inimicus species can contract common

saltwater parasites, but tend to be less susceptiblethan many other fish. Cryptocaryon orAmyloodinium infestations can be controlled by astandard formalin bath or hyposalineenvironment. Scorpionfish occasionally sufferfrom intestinal cestode or nematode worms,losing weight even though they eat frequently.Suggested treatment is oral administration offendbendazole at a dosage of 100 mg perkilogram of fish. The fish should be weighed toestablish the correct dosage. Do this by catchingthe fish in a small, fine mesh net and cover withanother net so the fish does not flip out whenplaced on the scale. Be careful, as devilfish arespiny and get tangled, especially in coarse meshnets. After weighing the fish subtract the weightof the nets, figure the necessary amount of drug,and place the dose in a piece of fish, if the fish willaccept non-living food. If not, and you have accessto a fish tranquilizer such as MS222, anesthitizethe fish and deliver the drug down the gullet andinto the alimentary tract by means of a syringe.Remember, you must be very careful whenhandling scorpionfish because of theirvenomous spines.

It is common for devilfish to swim franticallyagainst the side of the bag during shipping, thusinjuring the tip of the lower jaw. Some collectorsand wholesalers discourage this by putting a layerof fine coral sand in the bag. I would not purchasea specimen with such a wound until it has healedand the fish is eating. Often a nodule developswhere the wound was. Although unsightly, such anodule will not interfere with maintaining the fish.

A devilfish may also swim with its snoutpressed against the side of the aquarium. Thishappens if the tank is undersized, or lacks enoughsuitable substrate so the fish can bury itself. Adevilfish may swim incessantly if it is beingharassed by tankmates or the water movement istoo strong. This behavior can also cause damageto the lower jaw. It may be possible to curb thisbehavior by taping a 10 inch (25 cm) wide sheetof black plastic along the outside bottom edges of the aquarium.

Inimicus didactylus

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The Spiny DevilfishThe most commonly encountered member

of this genus is the spiny devilfish, Inimicusdidactylus. Coloration can vary greatly fromindividual to individual in this species, rangingfrom dark brown through light brown, pink, andred, to bright orange. The inner surface of thepectoral fins can be yellow or white, with a blackarea streaked with white beginning at the axil andextending to the middle of the fin. There is also adark border at the margin of the fin broken up bylight spots. Juveniles may have one or twofilamentous rays extending from the upper marginof the pectoral fins. Adults attain a maximumlength of just over 7 inches (18 cm). In the wildthis species ranges from Thailand to Vanuatu,north to southeast China and Micronesia.

The spiny devilfish is most often found onsand, mud, and mixed sand and rubble bottoms atdepths from 10 to over 260 feet (3 to over 80meters). In some areas it has been observedamong macroalgae and sponge. During the day itrests on or buries itself in the soft bottom. In thisposition it can capture small fish that swim nearenough. At night it emerges to hunt for food.When it displays at a rival or potential predator, itspreads its pectoral fins down and forward andexpands its tail. In some cases it also curls thecaudal peduncle to one side.

This ends our brief look at the genus Inimicus.For those of you looking for something out of the ordinary that is not only unusual inappearance but also interesting in behavior,consider one of these odd scorpionfish. Goodluck and happy fish-watching.

Speak of the Devil:Fish in the genus Inimicus


that it survived in the Mediterranean Sea. It wassuggested that this Caulerpa had been geneticallymanipulated or had mutated while in Europeanaquariums before it escaped into theMediterranean. This strain of Caulerpa taxifolia ismore tolerant of cool water than most Caulerpaspecies, and it reproduces only asexually byfragmentation. New DNA and allozyme markerstudies, along with temperature studies, haveconfirmed a natural population of C. taxifolianear Brisbane, Australia having similar traitsthat could have been the source.

The proposal to ban the entire Caulerpagenus rests partially on the concern that aquaristsand enforcement staff will not be able todifferentiate C. taxifolia from other Caulerpaspecies. Although C. mexicana can sometimes beconfused with C. taxifolia, the rest of the Caulerpaspecies are different enough that simple linedrawings would be sufficient to identify them withcertainty. Another concern is that other Caulerpaspecies could mutate to be more tolerant ofcooler conditions. This possibility is less likelynow that it appears that this did not happen inthe Mediterranean, as discussed above. Globalwarming may make southern California moresuitable to many species of sub-tropical organismsthat could invade this region, and this can’t becured by legislation. There are already fourspecies of Caulerpa native to the Gulf ofCalifornia that could migrate up the coast ifthe climate moderates.

I must express my concern about themotives of some of the players in this drama. Anote in the August 2000 issue of Nature by RexDalton mentions the continuing debate over whoshould control the multi-million dollar eradicationeffort. In an area that usually has little funding, the“Killer Algae” publicity may be generating awindfall of grant and research money. Agenciesinvolved include the California Water QualityBoard, the U. S. Department of Agriculture, theUniversity of Tennessee Institute for BiologicalInvasions, the University of California-DavisBodega Marine Laboratory, the Invasive SpeciesAdvisory Committee, and the Aquatic NuisanceSpecies Task Force, to name a few. Politiciansmay also use this bill to appear ecologicallysensitive while not offending major campaigncontributors such as shipping, lumber, energy, or other industries. Historically, most of theintroductions of non-native marine organismshave been due to encrusted ship hulls and ballastwater. To stop all such introductions the agenciesshould curtail shipping. Of course this is not goingto happen.

Aquarists should be concerned that this issuecould be the first of a series of generic bans oforganisms considered to be potentially invasive.Such bans could devastate the aquarium hobby. I understand the motive behind banning Caulerpataxifolia, but I disagree with the extension of theban to cover all Caulerpa species. The loss ofCaulerpa would not cripple the pet trade, but itwould be a dangerous step toward banning allexotic organisms. I encourage all concernedaquarists in California to contact their localrepresentatives to let them know aquarists areconcerned about the passage of Bill #1334.

Caulerpa Ban in California


Results and DiscussionAs of this writing, we have spawned and

reared eighteen marine fish species in oursystems, including nine species of goby. Ourability to adapt commercial aquaculturetechniques to a laboratory setting has enabled


A System for Laboratory orCommercial Culture of Gobiid Fishes

Caulerpa taxifolia obtained from hydroponics (in anutritive medium) exhibits its strong roots

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Caulerpa mexicana has often been mistaken forCaulerpa taxifolia.

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us to look at early development as a source ofcharacter data that has not previously beenused in the structuring of gobiid systematics.Detailed information on characters beinginvestigated and their possible implications ingobiid systematics can be found on the websiteof the Gobioid Research Institute:http://home.att.net/~gobiidaePlease contact Aquarium Systems, Inc. at 800 822-1100 for a list ofreferences related to this article.

ISSN 1045-3520FREE

Volume 18 Summer 2001

Rabbitfish such as the Foxface rabbitfish (Siganus vulpinus) are useful in algae control.

Reef Tank Nuisancesand Controlsby Michael Paletta

Reflections on the 9thInternational CoralReef Symposiumby Rand Kollman

I recently had the opportunity to attendthe 9th International Coral Reef Symposiumin Bali, Indonesia, a conference presentedand attended by scientists from around theworld. I was drawn there by my passion forthe oceans and coral reefs. After one shortweek I was more informed, and moredisheartened, about the state of coral reefs everywhere.

Threats to coralThreats to the world’s coral reefs are

numerous and serious. Instances of coralbleaching events have increaseddramatically. The zooxanthellae algae withincorals produce food and oxygen, but thesealgae are expelled from the coral whenwater temperature rises, resulting inbleaching and often in death of the coral.Global warming is thought to be the maincause of such events. Destructive fishingpractices and overfishing is ultimately badfor local fishermen and recreational usessuch as sport fishing and diving. Draining ofwetlands, coastal farming, and destruction ofnatural vegetation result in loss of filtrationof the fresh water flowing from the land.Runoff from towns, farms, and industry,along with deforestation, send pollutantsand sediments out toward the coral reefs.

Corals have lived for millions of years.Many experts believe that reefs go througha continuous cycle of thriving and dying, andthat these disturbances and renewals arecommon and can even add to the diversityof life found on and around reefs. However,if steps are not taken soon to alleviate thethreats to the world’s coral reefs they willcease to exist as vital communities. A timecould come when coral reefs are composedof dead coral skeletons, not living animals.This would be a sad ending, particularlywhen this Coral Reef Symposium hasproven that we now have the knowledgeand technology to alleviate at least some ofthese threats.

With the long-term success of thereefkeeping hobby has come increasingknowledge of coral parasites, predators, andcompetitors that didn’t exist in old saltwatersystems. One recently discovered parasite is atiny starfish (Asterina anomala) that is capableof inflicting as much damage in a closedsystem as a crown-of-thorns starfish can doto a reef. It never grows larger than threequarters of an inch in diameter, and so canhide inside a coral colony, coming out only atnight to feed on the polyps. It is beige to grayor even mottled red, and very hard to seeinside a coral. Unlike other starfish it hasseven legs, unequal in size. It feeds on smallpolyp stony corals, soft corals, and large polypstony corals like Euphyllia and Lobophyllia. Itseems to prefer small polyp stony coralsStylophora and Seriatopora, but if they are notpresent will consume Acropora and evenBlastomussa corals.

©2001 Aquarium Systems, Inc., Mentor, OH - Printed in U.S.A.Continued on page 3

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These starfish reproduce rapidly and canoverrun a tank unless they are controlled.They feed at night, and can be plucked offcorals when feeding, but this must be donerepeatedly or they will come back in force. Itmay be necessary to use a natural predatorsuch as the harlequin shrimp (Hymenocerapicta) to eradicate them completely. Indeed,the starfish might be a problem now becauseof decreased numbers of harlequin shrimp inthe wild. The starfish appears on live rockcoming from many areas, but the majorityseem to originate in Fiji. It may be a goodidea to quarantine live rock and coralsbefore introduction to the display tank. Asingle Asterina starfish can completelyconsume a medium sized Acropora orEuphyllia in a few days.

Flatworms also frequently arrive with liverocks or coral colonies. Some will consumeboth coral tissue and zooxanthellae, and canbe detected only by following the thin threadof dead tissue in a coral colony. Such damagemay not kill a coral colony, but may provide a




Book Review:

Aquarium Corals -Selection, Husbandryand Natural Historyby Eric BornemanReviewed by Dick Perrin of Tropicorium, Romulus, MIwww.tropicorium.com

Books with fresh insights and newinformation are the lifeblood of the reef hobby,but it is rare indeed when a book comes alongthat challenges some of our most time-honored concepts. “Aquarium Corals” is sucha book, with 464 pages and 765 beautifullyreproduced photos by such distinguishedphotographers as Scott Michael, Janine Cairns-Michael, Paul Humann, and Alf Jacob Nilson.This is not a book for the novice reefkeeper,but an experienced aquarist will find a wealthof information in every chapter.

The forward by Dr. J. E. N. Veron is asinteresting as it is surprising. Dr. Veron is ChiefScientist at the Australian Institute of MarineScience and the author of “Corals of theWorld.” Scientists have traditionally heldhobby aquarists in poor regard and placed littlevalue on their efforts. Dr. Veron, however,believes that reef aquarists may make realcontributions to the body of knowledge aboutcorals and their successful husbandry throughobservations of their own aquaria. He alsobelieves that reefkeepers can raise publicawareness of the threats to natural reefs andthe efforts that are being made to preservethem. This forward will make seriousreefkeepers feel good about their hobby.

The introduction gives some history of thehobby, along with the author’s philosophy thatsuccessful coral husbandry involves more thanspecies identification, flow rates, and lightingrequirements. It should include understandingwhat corals are, where they live, how they are

nourished, and what they do to survive in avery competitive environment.

Chapter OneIn Chapter One, Reef Worlds, the beauty,

diversity, and wonder of coral reefs isillustrated. Fossil records, reef types, coraldistribution, reef zones, and nearbycommunities are discussed.

Chapter Two Anatomy Lessons describes polyp types,

structures, and anatomy, including colonyformations and growth forms.

Chapter Three Zooxanthellae, contains the best discussion

of this topic in print today. We who keepcorals depend on zooxanthellae much morethan we realize, and this chapter provides thebest description to date of our ally in coralgrowing. This chapter is easily worth the priceof the entire book.

Chapter FourFood and Feeding, is my favorite chapter. It

explains why corals need more than properlight, water quality, and movement: they needfood! Reef explorer C. M. Yonge discussed theapparent feeding ability of corals in 1931.“When an animal possesses an organ or set oforgans, which perform certain functions withperfect efficiency, it can be taken as axiomaticthat such organs are used.” This chapter gives aformula for making coral food and directionsfor using it. The benefits provided by refugiumsare also discussed.

Chapter Five Secret Lives, Competition, and

Reproduction, is a journey into coral strategiesfor aggression and defense. This information isparticularly valuable to those aquarists who

As a saltwater aquarist,you take your hobby veryseriously. And when it comesto your prized marineanimals, you demand onlythe best... the very bestlights, filters, skimmers, andfoods. Your salt selectionshould be the very best too.

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Continued on page 4

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site for secondary infection. The best way to rid a tank of flatworms is to introduce amandarin fish (Synchiropus splendidus), whichalso will consume other micro-fauna in thetank. Although leopard wrasses(Macropharyngodon meleagris) will eatflatworms they often must be de-wormedfor trematodes with Flagyl® before they areintroduced into the tank.

Bristle worms and fire worms are wellknown enemies of the invertebrate aquarium.They are frequently stowaways on live rockor corals, and eat virtually any sedentaryinvertebrate, but are particularly fond ofEuphyllia and all types of soft corals. Smallerworms live in the substrate and multiplyrapidly. They generally reach a length of twoto three inches, and so don’t pose much ofa threat to the general invertebratepopulation. They perform the useful task ofaerating the substrate, and should not beremoved. However, they can rapidlyconsume a specimen coral that has alreadybeen damaged, especially if it is on thebottom of the tank.

Larger, more dangerous worms live in thelive rock. Individuals of the Nereis and Eunicespecies can attain lengths of six to sixteeninches. They come out at night to feed, so thisis the best time to try to remove them. It ispossible to pull them from their holes usinghooked tweezers, but the part of any brokenworms remaining in the holes will grow into afull sized specimen. These worms aresensitive to even very slight vibrations, andwithdraw into the rock so quickly it is difficultto catch one out of its hole. The best controlis by means of natural predation. Harlequintuskfish (Choerdon fasciatus) will consume eventhe largest bristle worm without damage toitself. Green bird wrasses (Gomphosus varius)will take care of smaller worms.

Predatory mollusks can also betroublesome in reef tanks. This includescowries, whelks, cone shells, some snails, andmembers of the Volutidae family. Althoughthey may resemble typical herbivorous snailsintroduced to control algae, they are actuallyaggressive carnivores that attack all varietiesof invertebrates. The most dangerous possess

Reef Tank Nuisances and Control


a venomous radula that injects a rapid actingpoison into prey. In some species the radulahas developed into a drill that can borethrough a shell. In general these mollusks arevery specific in the choice of prey. One of themost interesting of these animals is the Raparapa snail. It eats only Sarcophyton andLobophyton leather corals and Sinularia fingerleather corals. It bores into the coral stalkwhile it is small and then slowly eats the insideof the coral. I have been troubled by themonly twice, and in each instance I assume theyarrived already inside the coral at purchase. Iknew they were present only when a leathercoral stalk turned yellow and the polyps didnot expand. On closer examination I found asmall healed incision on the stalk. When Ipushed on the stalk it broke open, revealingthe snail inside. I removed the snail and thecoral regained health in a few weeks.

Unlike the Rapa snail, most othermollusks are easy to spot and remove.Although they emerge at night, they are slowmoving and can easily be picked off the corals.Be careful to avoid the poisonous radula. Iremove them with a large pair of tweezers,just to be safe.

Another parasitic mollusk is thepyramidellae snail, about the size of a grain ofrice. It enters a Tridacna clam through thebyssus opening, and can weaken the clamenough to kill it. The best way to eradicatethis snail is to introduce a six line wrasse(Pseudocheilinus hexataenia) or a Pseudochromisspringeri, both natural predators.

The previously mentioned pests occurfrom time to time, but one pest will bepresent in virtually every tank: Aiptasiaanemones. They reproduce rapidly and alsoburn anything that comes in contact withthem. Again, the best remedy is a naturalpredator. The most efficient is the blackbanded butterfly, Chaetodon striatus. These fish

are very hardy, and will remove everyremnant of the anemones without botheringthe corals. Nudibranchs of the genus Berghiawill also remove Aiptasia, but will require twoto three months to do it. Peppermint shrimp (Lysmata wurdemanni) have beenrecommended by some people to controlAiptasia, but I have had no success with them.

The majano anemone (Anemonia sp.) is also a pest. This little green anemoneclosely resembles a miniature bubbletipped anemone, but reproduces quicklyand burns other life forms as Aiptasia does.Centropyge, Apolemichthys, and Pomacanthusangelfish all consume this anemone, but arealso fond of many corals, so they must bewatched carefully.

Other big nuisances in a reef tank are notanimals, but algae. Valonia macrophysa orbubble algae reproduce rapidly and canovergrow corals or grow under soft corals todislodge them. Rabbitfish (Siganus punctatus, S.puellus, and Lo uspi) or Red Sea sailfin tangs(Zebrasoma desjardinii) can be used toeliminate Valonia algae. The tang is aggressiveat plucking these algae from even the most

Carnivorous starfish (Asterina anomala) can reproducerapidly in a reef tank.

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Mandarin fish (Synchiropus splendidus)

Photosynthetic flatworms in a reef tank.

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Continued on page 4

reproduce corals by dividing them, as somespecies will emit toxic chemicals that couldendanger other animals in the tank. Chartsshow relative toxicity of corals to fish andother coral species. There is also a descriptionof sexual and asexual reproduction here.

Chapter Six Taxonomy describes the way species are

identified, classified, and named to minimizeconfusion. Serious reefkeepers should learnabout scientific names to be as precise aspossible when discussing aquarium inhabitants.

Chapter Seven The Corals discusses the families, genera,

and species of interest to aquarists. This is the largest chapter, with excellent photos,describing each species and its special needs.It provides detailed information about the care and maintenance of each speciesdescribed. This information will be of value to many aquarists.

Chapter Eight Husbandry deals with several different

methods for maintaining reef aquariums,including the Berlin method, the Jaubertmethod, and algal turf scrubbers. There is anextensive, in-depth discussion of lighting, aswell as water movement and the benefits ofsurges. Plans for constructing a Borneman flushdevice are included.

Chapter Nine In Water Chemistry the author puts

forward his view that the best test for waterquality is the practiced eye of theexperienced reefkeeper. However, thesuccessful aquarist should know something

Aquarium Corals - Selection, Husbandry and Natural HistoryContinued from page 2

about water chemistry, additives, andtesting. Accurate, up to date informationabout water chemistry is long overdue, andproves in some cases to be the opposite oflong held beliefs and anecdotal experience.

Chapter Ten Care and Handling offers tips for selecting

viable specimens, for quarantine protocols, andfor methods of low stress introduction intothe aquarium. Also covered here is the use ofsuper glue and epoxy for coral placement. Theauthor recommends selecting captive growncoral when it is possible.

Chapter Eleven Coral Health is an ambitious summary of

coral health problems, with suggestedsolutions. The use of antibiotics and similartreatments is discussed, and solutions toproblems caused by algae are offered.

Chapter TwelveChapter Twelve discusses Conservation.

Many natural reefs are at risk due to humandisturbance or other causes, but there arevarious campaigns for public awareness andconservation in place, including a growinginterest in captive reproduction of corals. A list of conservation groups and a list ofcoral propagators is presented here, as well as a glossary of terms and an extensive bibliography.

Finally, I must state that I have no personalfinancial stake in this book, but I want otherswho have reef tanks to know about this goldenopportunity to improve their skills andknowledge. I applaud the author’s skill, effort,and determination in producing a book of suchoutstanding quality.

Upcoming Events

2nd International Conference on MarineOrnamentalsNovember 27 - December 1, 2001, WaltDisney World Resort, Lake Buena Vista,FloridaFor more information visit:www.ifas.ufl.edu/~conferweb/MOor call: (352) 392-5930

inaccessible spots. Emerald crabs (Mithraxsculptus) will also eat these algae, but maymove on to the corals when the algae are gone.

Hair algae of the genus Derbesia are alsocommon pests, growing best when there isa high level of phosphate in the aquarium.Reducing the phosphate level and addingemerald crabs will help control Derbesia.The crabs will pluck the algae from therocks if it is cropped, so you must cut offthe tops of it first.

For general control of algae I prefer a mix of different species of tangs and rabbitfish.Examples of tangs are Yellow tang (Zebrasomaflavescens), Sailfin tang (Z. veliferum), Purpletang (Z. xanthurum), and Atlantic Blue tang(Acanthurus coeruleus). Rabbitfish are of thegenus Siganus. A good variety allows every

Reef Tank Nuisances and Control


The Black-banded butterflyfish (Chaetodon striatus) is a good choice for Aiptasia anemone control

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individual to find something to eat. Althoughsome people will recommend what areloosely termed lawnmower blennies, I prefernot to use them as they are unpredictable.Some will consume algae, but some will grazeon zooxanthellae. A single individual may eatboth if food is scarce. Examples of theseblennies are Salarias fasciatus, Parablenniusmarmoreus, Escenius bicolor, E. gravieri, andOphioblennius atlanticus. Turbo, Astrea, andTrocheus snails will also eat algae, but youneed a lot of them. The snail I prefer to use iscalled a zebra or red-banded snail, recentlybrought in from Indonesia. It is the same sizeas the Astrea snail, but it moves five timesfaster, and eats all the time. I wholeheartedlyrecommend this snail.

This has been just the start of what maybecome a long list of reef tank nuisances.New pests are being classified now, some ofwhich are microscopic, and methods of

Juvenile Atlantic blue tang (Acanthurus coeruleus) inBonaire.

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eradication have yet to be developed. Thisarticle is just the beginning.

Editor’s Note: Michael Paletta is the author of “The New MarineAquarium.”

ISSN 1045-3520FREE

Volume 18 Fall 2001

Closeup of an educational reef aquarium.

A Miniature Coral Reeffor the Classroomby Thomas Frakes, Technical Consultant Aquarium Systems, Inc.

Solving Problems inSeahorse Cultureby Todd Gardner, Hofstra University Biology Department

More than twenty million seahorses are tradedworldwide each year, and there is every indication thatthis number is increasing. Although the largest portion isdestined for use in Chinese traditional medicine,substantial amounts also go to shell shops and theaquarium trade. Their low fecundity, monogamousmating behavior, and limited species ranges all placeseahorses in a precarious ecological position. Thesustainability of this fishery has not been fullydetermined, but for many species it is very likely being exceeded.

Seahorses have been spawned and reared incaptivity for many years, but a simple, effective, andreliable culture protocol is still needed. Those that havebeen published are either overly complex or lackessential details to protect the author’s proprietarymethods. Large scale high-tech aquaculture operationsmight relieve some of the stress on wild populations.However, many of the species at greatest risk of over-harvesting are collected by subsistence fishermen inisland nations like Indonesia and the Philippines. ProjectSeahorse has organized an initiative to teach thesefishermen aquaculture techniques that utilize simple andinexpensive equipment. This would benefit the localfishermen and the wild seahorse stocks, as well as thehome hobbyists who would love to raise the youngseahorses inevitably produced as a result of goodseahorse husbandry. My purpose here is to report onpreliminary rearing trials and some solutions toproblems I have encountered in my investigations.

Two of the biggest problems encountered inrearing seahorses are finding a nutritious first food andpreventing the gas bladder dysfunction that can affectmore than half a brood within the first few days of life,trapping them at the surface where they eventually die.A program is underway at Hofstra UniversityAquaculture Laboratory in Hempstead, New York tofind solutions to these problems.

Newborn seahorses will eat only live food. Artemiahas been the most popular choice for live food becauseof its availability and convenience, but it is separatedfrom ocean food webs by several million years ofevolution. It is not surprising that marine organisms arenot well adapted to digesting and utilizing Artemianutrients. Copepods, however, are probably the mostabundant multicellular organisms in the oceans, and areheavily exploited by innumerable marine species. Theyhave been shown to be nutritionally superior to Artemiaas a food for larval and juvenile marine fish. It isgenerally accepted that this is because of the relativelyhigher level of highly unsaturated fatty acids (HUFAs) incopepods compared with Artemia. Eicosapentaenoicacid (EPA) and docosahexaenoic acid (DHA) areparticularly important. Although a number of enrichingproducts are available to enhance the nutritional value

In recent years there has been a blossoming ofinterest in the mysteries of the ocean, and particularly inthe ecology of coral reefs. Coral reefs are oftencompared to the rainforests in the scope of theirbiological diversity, as well as their precarious positionbecause of increasing human encroachment into theirfragile world. Reports of reef degradation, bleaching,and destruction continue to make headlines. Theecology of reef organisms can be studied through fieldresearch, of course, but this is not practical forbeginning students. A marine reef aquarium is the logicalchoice for classroom lessons about coral reef ecology.

As recently as fifteen years ago, it was consideredto be impossible to keep corals in captivity. Marine fishaquariums were considered to be difficult to maintain,and invertebrate reef aquariums even harder. Prior tothis time, some avid hobbyists and scientists kept reefinvertebrates, but few people understood many of theconditions that were necessary to maintain andreproduce corals. This has all changed. Now aquaristskeep beautiful coral gardens that often require regularpruning to keep the corals from outgrowing their

©2001 Aquarium Systems, Inc., Mentor, OH - Printed in U.S.A.Continued on page 3

miniature ocean. Dead, bleached coral skeletons asaquarium decorations are a thing of the past. They havebeen replaced with living rocks encrusted with purplecoralline algae, sponges, tunicates, and other benthicorganisms, along with hard and soft corals that cangrow at an amazing rate.

How is this possible? In this relatively short fifteenyear period methods and equipment for keepingdelicate reef animals and plants have evolved throughthe contributions of thousands of marine aquarists.Also, knowledge of the environmental requirements ofindividual species has grown. All this has made possiblethe design of complete life support systems such as theMirabello Reef Kit Aquarium.

The Educational Reef AquariumWe have put together a complete package for the

educational market that is based on the Mirabello 30aquarium, incorporating all the equipment necessary tostart a successful reef ecosystem. It is based on a 30liter glass aquarium with a built-in filter and a hingedlight hood. A multi-stage filter system built into the backof the tank performs mechanical, biological, andchemical filtration. The internal pump provides theturbulent water movement that is essential forstationary reef organisms. A Visi-Therm heater isincluded in the filter section. The high output compact

Continued on page 2




Aquarium Systems is a Marineland Company

Lined seahorse (Hippocampus erectus) in courtship.

Longsnout seahorse (Hippocampus reidi) after givingbirth.


of Artemia, resulting in a fatty acid profile similar tocopepods, use of these products still has not achievedthe success gained by using copepods in terms ofgrowth, survival, and overall health of cultured fish.Unfortunately, in spite of the abundance of copepods,we have not yet developed a technique to culture themon a scale large enough to be economically feasible.Collecting copepods from the wild for use as food inaquaculture is labor intensive and cost-prohibitive, andwild copepods may also be accompanied by undesirableparasites and fouling organisms. Moe and Young werethe first and only ones to rear the larvae of Frenchangelfish, Pomacanthus paru, in the 1970’s using wildplankton composed mostly of copepods. Although theyraised thousands of fish they made no profit, partiallybecause of the high cost of obtaining sufficient numbersof copepods.

A detailed experiment to examine the benefits ofcopepods and Artemia in seahorse culture has beendesigned at the Hofstra University aquaculture lab andwill be conducted in the next few months. Threepreliminary rearing trials have already been conductedto investigate feeding regimes and filtration designs thatmight be used in the experiment.

Four pairs of Hippocampus erectus were collectedoff Long Island, New York, and housed in a 55 gallonaquarium. Filtration was by means of an undergravelfilter under 2 inches of crushed coral, driven by a powerhead, and an Eheim canister filter with activated carbonand nitrate sponge from Kent Marine. The broodstockwas fed frozen mysid (Mysis relicta) and chopped shoreshrimp (Palaemonetes pugio) four times a day. A lighttimer provided a 15 hour day. Courtship behavior,which will not be discussed in this article, was observedvirtually every morning. Receptive males indicate theirreadiness to spawn by a swollen pouch. Actualcopulation was rarely observed, but if the same malewas seen with a swollen pouch for more than 3 days, hewas considered to be pregnant and was placed in therearing tank. Occasionally the pouch would deflate afew hours later, but most of the time this criterionindicated an actual pregnancy.

Rearing trials were conducted in standard 10 gallontanks, each containing an entire brood of Hippocampuserectus. Small air driven foam filters were used in trials 1

and 2. In trial 3, one end of the tank was sectioned offwith a tank divider having 500 micron mesh screeninginstead of the plastic insert. The resulting compartmentwas filled with small plastic beads that were slightlynegatively buoyant. The beads were kept in motion bymeans of aeration, forming a simple fluidized bed filter.An 8 inch air diffuser was placed on the floor of thetank near the filter compartment to keep the seahorsesfrom being drawn into the netting. This method ofaeration created a vertical circulation pattern that keptmost of the newborn seahorses from becoming caughtat the water surface, as had happened in trials 1 and 2.In each trial, live Isochrysis galbana was maintained at adensity sufficient to keep a 2 cm secchi disk out of sightat a distance of 50 cm. All tank bottoms weresiphoned daily.

In the first trial, Artemia salina nauplii enriched withSuper HUFA from Salt Creek, Inc. were offered as theexclusive food. There was 100% mortality in this tankafter 2 weeks. In the second trial, copepod-dominatedwild plankton (CDWP) was fed for the first 2 weeks,after which time the diet was abruptly switched toenriched Artemia salina. After 60 days 190 seahorseswere counted. In the third trial, CDWP was offered for3 days, followed by enriched nauplii of Artemiafranciscanis. After 60 days, 214 seahorses were countedand moved to a 40 gallon grow-out tank. Food densitieswere maintained between 0.5 and 2 per milliliter.Synthetic sea water in all experiment tanks was madefrom Instant Ocean synthetic sea salt, maintained at 25parts per thousand. Artemia cysts were decapsulatedwith household bleach (5.25% sodium hypochlorite).Isochrysis was cultured according to the method outlinedby Hoff and Snell in the Plankton Culture Manual.

Obviously, these preliminary trials do notrepresent controlled experiments. Survival percentagesfor trials 2 and 3 could not be calculated because initialbrood size was not counted. All that can be said is thatcopepods appear to play a crucial role in the early dietof H. erectus. The planned controlled experiments aredesigned to determine the effects of variations of thecopepod/Artemia feeding regime during the first week,and on the growth and survival of H. erectus after onemonth. These results will be discussed in a futureSeaScope article.

I did not have a problem with parasites associatedwith wild plankton, but a number of other pests wereintroduced into the tanks. The worst of these werehydroids, gammarid amphipods, and gastrotrichs. Thehydroids probably came in as larvae or medusae, andwithin a few days fuzzy colonies could be seen on the

tank walls. Although their stinging tentacles can injure orkill small seahorses, the bigger danger is fromcompetition for food. By the time a hydroid colonyreaches a few inches in diameter it can become a seriousdrain on the plankton supply. We observed threegenera of hydroid, Bouganvillia, Tubularia, and anunidentified species. Scraping colonies from the walls isonly a temporary solution, as numerous new coloniesappear as a result of fragmentation.

We cultured these hydroids in separate tanks tolearn more about them. A tiny nudibranch appeared insome hydroid tanks after a few weeks of culturing.White egg clusters also appeared among the hydroidtentacles. The 6 mm long nudibranchs were observedfeeding on the tentacles of all three hydroid species.After a month, hundreds of nudibranchs could be seenin the tanks, and virtually all of the hydroids had beenconsumed. Hydroid-eating nudibranchs such as Tenelliahave appendages called cerata on their backs. As theyfeed on the hydroids, or other animals like corals oranemones or jellyfish, they transfer the stinging cellsfrom the hydroid to their own cerata for protectionfrom any would-be predator. We hope that with thehelp of T. fuscata we will no longer have problems withhydroids in our rearing tanks.

Amphipods appeared in the tanks as small but fastgrowing juveniles. They are an important component ofa seahorse’s diet in the wild, but grow too quickly to usefor food in a culture tank, and they soon becomestrongly competitive for the plankton. They are bestremoved by siphoning and then can be used as anutritious treat for adult seahorses.

Gastrotrichs are an obscure phylum of free livingworm-like organisms that normally live in sediment. Ihave often seen large populations of an unidentifiedgastrotrich crawling on the skin of young seahorsesthat have been exposed to wild plankton. They maynot be parasites, but do seem to stimulate incessantscratching by the seahorse. They can be removed byfreshwater baths.

If you are interested in keeping or breedingseahorses, I encourage you to take some time toresearch their requirements before making a purchase.In many respects they are hardy fish, but they have anumber of unique needs that must be met if they are tothrive in a home aquarium. They must be in a non-competitive environment. Most fish are not suitabletankmates for seahorses. Seahorses will do even betterif they have been captive-bred. They will not have beensubjected to many of the diseases that contribute to thehigh mortality rate of wild-caught animals.

For more information, you can log on towww.seahorse.org where you will find a community ofhobbyists and professionals dedicated to responsibleseahorse breeding, husbandry, and conservation.

Solving Problems in SeahorseCulture

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fluorescent bulb in the built-in light provides a specialwhite spectrum that simulates the natural reef lightingnecessary for growth of the specially selected corals.The package also includes Instant Ocean synthetic seasalt, which makes superior synthetic saltwater whenmixed with pure water, and a SeaTesT hydrometer tomaintain proper salinity. Finally, the tank bottom iscovered with a layer of CaribSea aragonite sand thatprovides a natural habitat for a host of microorganismsthat help to process wastes.

LivestockIt takes more than hardware to make a successful

coral reef. A key ingredient of the Mirabello ReefAquarium is the specially selected package of liveorganisms. It includes a mix of six or more corals thatare compatible with the conditions in the system. Thisincludes mostly soft corals, but there are a few hardcorals that are also suitable. Several pieces of live rock,encrusted with live organisms, are also included to formthe reef structure, as is a bag of live sand. The live sandand rock are populated by a mix of small to microscopicorganisms that help to process wastes and balance thesystem. These include heterotrophic and nitrifyingbacteria, protozoans, worms, copepods, and more.Finally, because green algae can compete with corals fornutrients and space, a group of algae grazing organismsis included. The package of live animals is delivered tothe school by overnight express service after theaquarium has been set up with saltwater and is runningproperly. Organisms are packed in plastic bags withwater and oxygen and shipped in an insulated carton toguarantee live delivery.

The corals for this kit are raised in Instant Oceansaltwater by coral farmers. These expert aquarists haveselected compatible and representative types of coralsfor stocking the tanks from the hundreds that are nowbeing cultured in captivity. The corals are matched tothe levels of light and water movement available in theMirabello Reef Aquarium. Not all corals are suited tothese conditions. Reefs have many zones, from crashingwaves of the reef crest to the gentle currents of theback-reef or lagoon. This package simulates the back-reef environment, and the animals are selected to suit it.

Once established, the Mirabello Reef Aquariumbecomes a unique tool for teaching students about thebiological, chemical, and physical processes that affectreefs. These lessons can be on many levels, from thebasics of salinity to the more complex nutrient balancebetween nitrogen, phosphorus, and calcium. Simplelessons can be taught on photosynthesis, as well asdemonstrations of the more complicated issues ofaggression and competition.

PhotosynthesisThe driving force for life on the reef is

photosynthesis. The growth and survival of tropicalreef-building corals are dependent on the symbiosisbetween the coral animals and the single-celled algaecalled zooxanthellae that live within the corals. Withlight, these algae cells provide most of the nutrientscorals need for growth. This successful relationshippermits the corals to prosper and build the massivestructures we call coral reefs. Micro- and macro-algaealso use light for photosynthesis and compete directlywith corals. In general, algae grow faster than corals, andwould overrun reefs if not controlled. A broad mix ofherbivorous fish and invertebrates maintains the balancebetween corals and algae in the wild. Within theconfines of our small aquarium we use lowly snails toperform this vital function. This equation is furthercomplicated by the growth of coralline algae, which

A Miniature Coral Reef for theClassroom


encrust over rocks and tank walls and prevent theattachment of green algae. Generally purple in color,these algae are essential to reefs, because it has beendiscovered that the larvae of many hard corals cansettle only on surfaces that have a coating ofcoralline algae.

Temperature, Light, and WaterMovement

The importance of physical factors such astemperature, lighting, and water movement can betaught using this model. Sustained temperatures above90 degrees Fahrenheit have been recorded incatastrophic coral bleaching events of reefs around theworld. Bleaching occurs when corals are under stress,and expel their zooxanthellae algae. The corals will diequickly if the algae are not replaced. Also, most tropicalcorals will not survive at temperatures much below 65degrees F. The Mirabello Reef is normally maintained attemperatures between 74 and 82 degrees. The Visi-Therm heater prevents low temperatures that couldoccur in some classrooms at night and over weekendswhen the heat in many school buildings is turned down.

Natural visible sunlight is a mix of colors from redto blue. Water absorbs red light first. Thus, photos ofreefs tend to appear bluish unless the photographeruses supplemental artificial light. The photochemicalprocess of photosynthesis by various chlorophyllsoccurs at more than one part of the spectrum. Manygreen plants and algae use the red end of the spectrummost efficiently. However, the chlorophyll in thesymbiotic algae in corals uses primarily the blue end ofthe spectrum. Lighting for modern reef aquariums hasbeen designed to be bluish-white to simulate the colorof light at a depth of fifteen to thirty feet. This seems tohelp corals grow, while it inhibits growth of undesirablenuisance algae.

The need for water movement in reef aquariums isoften overlooked, but adequate circulation is essentialfor healthy corals. Water is seldom still on the reefs.The surge from waves and the flow of tidal currentsconstantly bring nutrients past the corals, and also flushaway wastes. Without these currents many coralswould suffocate in their own slime. Common pumping

rates for reef aquariums are five to ten times the tankvolume per hour.

PollutionPollution is a major cause of reef damage around

the world. Wastes from sewage discharge and fertilizerrun-off are major contributors to reef degradation.Nutrients in these wastes are rapidly consumed by fastgrowing algae that can then grow over corals and killthem. Healthy reefs, again similar to rainforests, areactually poor in nutrients. A slow, steady influx ofnutrients is recycled through various organisms beforeit becomes sediment or is dispersed in the current. Inan aquarium nutrients have nowhere to go; any addedfood will accumulate. The Mirabello Reef package dealswith wastes in several ways. First, the mechanical filtertraps larger wastes that are removed by washing orreplacing the cartridge. The cartridge contains activatedcarbon that adsorbs some of the dissolved organiccompounds that can turn the water yellow, and alsoinhibit coral growth. These compounds are alsoremoved when the cartridge is changed. The beginningMirabello Reef does not include fish, which requireregular feeding, one of the major sources of aquariumpollution. It requires little or no food. This makes theMirabello Reef Aquarium ideal for the classroom. It canrun for days without attention, as long as the light is ona timer to give a twelve hour photoperiod. The primarymaintenance requirement is replacement of evaporatedwater with distilled water every few days.

Other ConcernsAnother issue to consider is the replacement of

depleted elements. As corals and coralline algae grow,they deposit calcium and other elements to buildskeletons. This often leads to a decrease in the level ofcalcium and trace elements in the water. The easiestway to counteract this condition is to make a one gallonwater exchange every two weeks using newly mixedInstant Ocean sea water. In a small way this simulatesthe flushing action of the waves and tides that constantlyprovides new water to the animals. The water exchange

The Mirabello Reef aquarium.

Continued on page 4

removes wastes not removed by other means, and alsoreplaces depleted elements.

Biological interaction between corals can also bedemonstrated. Corals have a number of defensestrategies. One such strategy is the nematocysts, orstinging cells. These microscopic harpoon-likestructures are used to capture food and to stingpredators and nearby competitors. Some hard coralshave long sweeper tentacles loaded with nematocyststhat kill neighboring corals to make room for growth.Many soft corals release toxic slimes that can harmother corals.

Coral reproduction is another interesting topic.Most corals raised for aquariums are created by meansof fragmentation or cutting of parent corals. Thesecuttings are then attached to new surfaces and continueto grow. This natural form of asexual reproduction canbe observed on the reef after a storm when brokencoral tips and branches begin to grow. Although somecorals are being reproduced sexually, this is still on theexperimental level.

Another benefit of this micro-reef is that it can bemoved. During long school breaks or extendedholidays, the water can be drained down to two inches,as in a low tide. The aquarium can be carefully movedto a new location, set in position, and the water gentlypoured back in, with little effect on the organisms.

Although this package was designed for use inschool classrooms, it would also be suitable for thenovice aquarist. The primary goal was to put togetherall of the critical components with a simple set ofprocedures that would result in nearly 100% success.We are currently testing alternative reef packages thatutilize the Eclipse I and Eclipse II twin light hoods withstandard Perfecto glass aquariums that are availablethrough local retail pet stores.

With this system, new aquarists can experiencesuccess at a modest cost and have the time to readthe latest theories on reef keeping while enjoying their aquariums, and before making the jump to a large reef tank.

Note: Mirabello Reef Kits for schools are currentlyavailable through Carolina Biological Supply Company,whose web site is www.carolina.com.

A Miniature Coral Reef for theClassroom


Book Review: Invertebrates, AQuick ReferenceGuideby Julian SprungReviewed by Thomas Frakes

When hobbyists set up reef tanks, theystock them with corals, live rock, live sand,fish, and grazing animals, but then theyencounter countless animals that arrive ashitchhikers. The obvious questions are whatare these, and are they safe for the reef. Some reefmanuals and coral guides list a few nuisance species, butdescriptions are brief and the scope limited. Field guidesonly list animals in a limited area, and give littlehusbandry information.

Because these creatures come from many placesand represent many phyla, it often takes a library ofguidebooks to identify a new specimen. The forms arequite diverse, and it is often difficult to know where tostart looking for identification. Tunicates can look likesponges, a comb jelly can mimic a flat worm, and someflat worms can be confused with mollusks.

We finally have an easy source of usefulinformation on many of these lesser animals that can befound in reef tanks. Invertebrates, A QuickReference Guide concentrates on organisms fromaround the world that have turned up in reef tanks.What I find most useful is the way this book answersthe questions hobbyists have about these hitchhiker

animals. How do they live? What dothey feed on? What special needsdo they have? Are they reef safe?Julian has done a wonderful job ofbringing together a broad mix ofcommon and not so common reeftank animals. He includes manyornamental specimens that may beoccasionally available through theaquarium trade, but are not wellknown, and he hopes to popularizethem. At the same time, commonlysold pests are revealed to be notappropriate for reefs.

Each animal is brilliantly shown in a color photomatched with a description. The format includesscientific name, common names, description, and noteson similar organisms. This is followed byrecommendations on suitability for reef tanks, hints forfeeding, special care requirements, and hardiness andlongevity in captivity. With over 650 photos, it is abeautiful book to browse through and to marvel at allthe strange beasts that could be found in your reeftank.

This book is highly recommended for all reefaquarists, beginner to advanced. It brings together thevast range of creatures encountered in reef tanks into asingle volume.

Invertebrates, A Quick Reference GuidePublished by Ricordea Publishing, Miami, FLDistributed by Two Little Fishies, Inc.Web site www.twolittlefishies.com240 pages, Suggested Retail Price $34.95

Mirabello Reef Livestock Package

A. Six corals from the following:1. Leather coral (Sarcophyton sp.)2. Tree coral (Capnella sp.)3. Mushroom anemones (Corallimorphs)4. Star polyps (Clavularia sp.)5. Finger coral (Sinularia sp.)6. Pulsing Xenia (Xenia sp.)7. Seamat or Button polyps (Zoanthus sp.)8. Small Polyp Stony hard branching coral

(Pocillapora damicornis)B. Assortment of grazer snails (~8) and hermit

crabs (~2)C. Three to four pounds of cured live rock D. Half pound of live sand

never too hot.never too cold.

Just ideal water temperature all thetime. With a touch of the Dual-Temp dial,you choose the ideal temperature settingfor your aquarium . Set it and forget it…no guesswork, no constant adjustment, no problem.

Dual-Temp Precision AquariumHeaters are, quite simply, the bestaquarium heaters available today. Andthere’s a Dual-Temp for every aquarium –freshwater or marine, five-gallon mini to75-gallon show.

Upgrade your old technology today…with Dual-Temp.

Dual-Temp™

P r e c i s i o n a q u a r i u m h e a t e r s© 2001 Marineland

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