The marine

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Authors Surtida, Marilyn B.

Download date 26/09/2021 09:48:22

Link to Item http://hdl.handle.net/1834/35044 aquafarm news • marine ornamentals

The

By MB Surtida Have you heard of divers be­ lengths at or near adult­ ing mesmerized by the hood is a good start be­ beauty of the ocean floor? cause the possibility of “That’s true,” says Henry ammonia toxicity is Young, a professional diver greatly reduced and future and hobbyist-entrepreneur growth still allows ad­ from Iloilo City (west central equate space for normal Philippines). “I didn’t know social interaction. As liv­ I had stayed too long until my ing animals, they load the buddy nudged me ‘awake’, filtration system, thus it is only to find I had very little impossible to say “this air left.” much inch per gallon” be­ Perhaps this is the rea­ cause of the wide variety son why to many, keeping of species. It is best to re­ marine fish becomes a con­ member that animals of suming passion despite the different species should complexity of simulating the not be placed in direct ocean floor environment in THE FILTERED AQUARIUM contact with each other. small, confined, aquaria. The is found left. Above it is the biofilter set Corals and anemones ex­ (the tube of the undergravel filter is visible in the middle). Aside from the belief in some pand and contract, thus, a The outside filter is at right cultures that fish bring good gap of at least 2" between luck, its therapeutic, soothing one fully expanded coral effect on modern man cannot be ignored.The size and shape of aquaria and the next must be allowed. Choosing the correct size, shape and ma­ Start right terial is crucial because it will spell the The water It is best to decide first what kind of success or failure of your hobby. It is im­The life of an animal is largely dependent aquarium you would want to maintain.portant to remember that seawater is cor­on the quality of the environment in which Would it be a fish tank? Or would it be rosive to most metals and aluminum init alives. Throughout the world, the chemi­ one for invertebrates with sea urchins,marine tank. Most all-glass tanks have cal composition of seawater is similar. octopuses, hermit crabs, anemones? oraluminum a alloy lids. If you do choose one, cross-section of living corals with shrimps,paint it first with a suitable primer and two worms, and other invertebrates? This coats of a good quality gloss paint to re­ decision would help you select the fishesduce corrosion. that would go with one or two invertebrates The shape and size of a marine tank is or the soft and hard corals that would goimportant because the filtering capacity into the “living reef” you would wantand to of course the number of fish that the put up. This basic decision would alsotank can carry will be determined by it. make you decide how much you want to A 20-gallon tank is a convenient start. invest as these selections have varying re­Dimensions (all glass pieces are 0.25” quirements as to feeding, filtration, andthick): 3 pieces of size 30" x 12.5" for even lighting. But it makes sense to get asbottom, front, and back sides: 2 pieces 12 much information as possible before mak­x 12.5" for left and right ends. ing the plunge by reading everything you Be careful not to overstock. With fish, can find and talking to dealers and success­an absolute maximum of 1" of fish length ful hobbyists. per 6 gallons of water based on estimated

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For your aquarium, you may cither willuse make more or less 25 gallons and it The undergravel filter is a perforated seawater or artificial seawater (now avail­ will be much easier to weigh out the plate, covered by a 2.75 to 4 inch layer of able in commercial quantity). chemicals. suitable , ideal quantities of coral If you decide to use seawater, gather Marine aquaria lose a significantgravel, coral sand, and a commercial buff­ it offshore in an area that has good tidal amount of water each week by evapora­ering material. In a down-flow set up, flushing and no obvious nearby sourcestion. of When this occurs, it leaves thepolluted but oxygenated water is drawn pollution. Look for live fish, crabs andseawater in your aquarium more salty. Thedownwards to the surface where colonies other life in the area. If they appear healthy,most convenient way to measure the saltof nitrifying living on the surface the water must be good. Filtering the content of seawater is to determine its sa­of the substrate particles break down ni­ seawater from and particulatelinity with a hydrometer. Follow the user'strogenous wastes. The drawback to bio­ material is a good practice. The best way manual. Another instrument that measureslogical filtration is that the process does to treat seawater before using it is to storesalinity is the refractometer. not remove waste products from the it for two to three weeks in a dark place. You can check the pH of seawater byaquarium but only transforms the waste Remove the water carefully so that the using a simple pH test kit. It should pro­compounds with very limited toxicity. sediments are not disturbed. Some duce a reading of around 8.3. A readingThese compounds accumulate in the hobbyists use the seawater immediately below 8.1 and above 8.5 may occasionallyaquarium and eventually have to be re­ without storing with a degree of successresult in problems in excessive ammoniamoved through a complicated filtration but small parasites may be introduced thisif filter system is not fully biologically ac­system or through the simple process of way especially if the seawater is not well tive or if there is a tendency to overfeed.periodic, partial water changes. filtered. Chemical filter. Many chemicals in the If you use artificial seawater, be aware Filtration water are not easily removed by that it differs from nature and all impuri­A good biological filter system is at the undergravel filter. Chemicals from the ties present in the makeup water becomeheart of every successful marine aquarium.water are removed by the process of ab­ part of the aquarium environment. FollowYou must know, understand, and work wellsorption. Synthetic pads and activated car­ the manufacturer’s instructions when youwith the basic principles of biological fil­bon are normally used in the canister of an mix the salts and the trace elements. If youtration. There are two basic types of con­external power filter. Carbon is cheaper but are just starting, you may mix directly taminants:in suspended, physical particlesan absorbing pad has the added advantage your aquarium, but if you have an estab­and dissolved chemical compounds. of its useful life being seen — the color of lished tank and changing water, it would Mechanical filter. Mechanical filtra­ the pad changes from white to blackish be best to mix the salts in a plastic pail. tion removes suspended particulate mat­brown when it has absorbed all it can. Wait until the solution clears and the ele­ter. It may utilize sand, gravel, floss, metalThus, you will know that the pad needs to ments are dissolved before adding the or plastic screens to strain particles frombe changed. In contrast, the effective life newly mixed water in the tank. the water. of carbon is not easy to estimate, and, once If you want to mix your own seawater, Biological filter. Nitrogenous waste “full” with adsorbed chemicals, is liable you may try the formula in an article matter by produced by all animals primarilyto release them back into the tank, thus Lyman and Fleming titledThe composi­ appear in the form of ammonia. Biologi­negating all its previous beneficial work. tion o f seawater in Journal of Marine Re­cal filter systems convert these dissolvedHowever, carbon can be extremely benefi­ search Vol 134, No 3 ( in grams for 1,000 waste products into progressively less toxiccial when used in small amounts and g water): substances by bacterial action. We shall changed weekly. discuss one type, the undergravel filter, Protein skimmers. Protein skimmers 23.477 or air-stripping devices remove harmful 4.982 shown below: waste products such as proteins, phenols, Sodium sulphate 3.917 and albumins. In air-operated units, a 1.102 0.664 column of enclosed water is fiercely aer­ Sodium bicarbonate 0.192 ated with very fine bubbles. The proteins Potassium bromide 0.096 and other wastes “stick” to the bubbles (a Boric acid 0.026 natural tendency of so-called “surface-ac­ 0.024 tive” dissolved organic molecules) and are Sodium fluoride 0.003 carried to the top of (he column in a stiff foam. This foam spills over into a plastic The formula makes up 1 cup, where it collapses into a murky brown liter solution. Multiplying each ingredient by 100 page 36

30 SEAFDEC Asian Aquaculture Vol. XXI No. 2 April 1999 The aquarium ... from page 30 Compatibility of fishes and invertebrates in marine (from Spotte 1993)

Animal group Sometimes incompatible with these groups Fishes 1 Angelfishes 1, 16, 27 2 Angelfishes (pygmy)2 3 Basslets 17-19, 21, 23 4 Blennies 19-19, 21, 23 5 Butterflyfishes 5 6 Cardinalfishes 17-19, 21, 23 7 Damselfishes 17-19, 21, 23 8 Dottybacks 17-19, 21, 23 9 Dragonettes 17-19, 21, 23 10 Drums 17-19, 21, 23 11 Eeltail catfishes 17-19, 21, 23, 27 12 Filefishes — 13 Gobies 27, 30 14 Hawkfishes 17-19, 21, 23 15 Jawfishes 17-19, 21, 23 16 Moorish idol 17-19, 21, 23 17 Morays 1 18 Roundheads 3, 4, 6-10, 13-15, liquid which can be discarded. Motor Compatibility 26, 27 driven protein skimmers are more expen­Compatibility between species -- and19 Scorpionfishes 3,4, 6-10, 13-15, 26, 27 sive but even more powerful and efficient.among individuals of the same species — 20 Seabasses is largely unpredictable. For example, two (anthiines, others) Selecting your fish individuals might be compatible if they dif­2 1 Seabasses (groupers) 3, 4, 6-20, 13-15, There are five criteria for selecting fish in fer substantially in size. Under different 26, 27 dealer’s aquaria: (1) immediate condition, circumstances, the same individuals might 22 Seahorses 17-19, 21, 23 (2) potential survivorship, (3) ease of care,get along only if their sizes are similar. 23 Squirrelfishes 3, 4, 6-10, 13-15. (4) compatibility with other animals, and 26, 17 (5) potential for growth. 24 Surgeonfishes and Feeding tangs 27 Accept fish from dealers with the fol­ Flake and freeze-dried feeds are readily 25 Triggerfishes 27, 30 lowing characteristics: available in marine aquarium stores. These26 Wrasses (small 3, 4, 6-10, 13-15, • Skin unblemished, bright, and shiny are good but must be supplemented with species) 26, 27 • Mucous coating transparent and not live food. The most preferred live feed isInvertebrates obvious, fins intact and unbroken, adult brine shrimp. 2 7 Crustaceans (crabs 1, 10, 12, 17, 18, starvation not extreme Remember not to overfeed as and shrimps) 20, 22-25 • Activity normal for fishes overfeeding fouls the water. The best way28 Sea anemones — • Swimming motions normal is to offer small amounts of food daily,29 Sea stars — 30 Sea urchins 12, 25 • Breathing slow and regular preferably four times. It is also good to • Fins in normal position know the feeding characteristics of your • Winner of territorial dispute fish. Planktivores and grazers feed almost Marine aquarium animals may be continuously during the times they arc maintainedac­ in good health for years on a For crustaceans, accept them when all their tive. But large carnivores such as grouperscombination of prepared feed, raw seafood, appendages are intact. Sea anemonesconsume large amounts at a single feed­and live brine shrimp. Offer a variety of should have their columns and tentaclesing, and then fast for long periods. Alwaysfeed daily. This encourages shy fish to eat extended fully while sea urchins shouldwatch the fish as they feed and make sure more consistently and may sometimes dis­ have erect spines. Sea stars should be ac­that all get enough food. Look for signs ofcourage aggressive companions from con­ tive. weight loss. suming more than their share.

36 SEAFDEC Asian Aquaculture Vol. XXI No. 2 April 1999 Feeding fish gather around the open the Philippines' DA-BFAR (Department fresh clam that was dropped into the of Agriculture—Bureau of Fisheries and aquarium. The uneaten portion Aquatic Resources) office, six CDT labo­ should he immediately discarded ratories are operational nationwide. CDT aims to be an enforcement tool to effec­ tively curb cyanide misuse in fisheries. IMA’s success in implementing its Cyanide Fishing Reform Program is attrib­ Resting brine shrimp cysts purchased uted to their development of effective part­ from dealers may be hatched at home to nerships with fishing communities, and to adult size. Using rice bran as food, they their advocation for policy reforms in both may then be reared to reproduce to have a source and consumer countries. continuous supply of live food. Policy measures (Barber and Pratt, 1997) include: the banning/restriction of Diseases export of vulnerable species; regulation in Bacteria and protozoans are the most com­ the import, distribution and use of cyanide; mon causes of infection and the most trou­ a firmer legal framework (such as a man­ blesome in marine aquariums. Watch out datory licensing and certification system); for these signs of diseases in your fish: loss public awareness campaigns in media and of appetite, loss of coordination, schools; strengthening consumer aware­ hemorrhaging of the skin, weight loss, loss ness; and establishment of a national sys­ tem for monitoring the live fish trade. of tissues in fin edges, inactivity, labored 'No' to cyanide ... from page 33 breathing, milky cloudiness of the body Enterprise development. CRMP or surfaces, open cuts that do not heal, and the Coastal Resources Management persistent red sores. of the target coral area. (When scared by Project is another non-profit, non-govern­ Generally, antibacterials and other sound or movement), the fish instinctivelyment organization whose work (though chemicals are readily available. But be sure dart back in the direction of their coral ref­ broader) closely aligns with that of IMA, that you follow label directions in theiruge. The barrier net, however, denies the in some aspects. A special project of the application. Most fish that are infectedfish access ..., giving the collector enoughPhilippines’ Department of Environment must be separated from the rest of the stock time to harvest them with scoop nets andand Natural Resources, it is funded by the in treatment aquaria. Remember that treat­ buckets. Unwanted fish are (then) released, United States Agency for International ments that exceed 12 hours are stressful to and the reef is left virtually undamaged." Development (the same organization that fish and not recommended. IMA gives the fisher enrollees the supports IMA). barrier nets initially for free and teaches AQD staff had a recent conversation References: them to make their own dirough an instruc­in Cebu, with CRMP Enterprise Develop­ tion manual. The one-week training coursement Officer Monette Flores. She talked Bower C E. 1983. The basic marine aquarium.includes three days of inland “classroom”about the organization’s current involve­ Charles C. Thomas Publisher USA. ment with Central Visayan coastal liveli­ Chadwick DH. Coral in peril.National Geo­ sessions on cyanide-free fishing technolo­ graphic 195 (1). January 1999. gies, post-harvest management of catches,hood projects which include mussel/oys­ Doubilet, D. Coral eden.National Geographic cooperative marketing and safe divingter culture andEucheuma seaweed farm­ 195 (1) January 1999. techniques. The next four days in water areing in Bohol, and a pending mangrove Haywood M and S Wells. 1989. The interpret project (for which she expressed she might manual of marine invertebrates. Salaman­for the actual experiencing of how the dif­ der Book. London. ferent technologies work. Follow up con­need SEAFDEC assistance). Moe MA Jr. 1982. The marine aquarium hand­tinues for months or years on such activi­ Contrasting Australia and the Philip­ book, beginner to breeder. The Norns tiesPub­ as organizing local fishing associationspines as aquarium fish exporters, she noted lishing Co., Marathon, Florida. that the former has a well-managed ma­ Spotte S. 1993. Marine aquarium keeping. andJohn cooperatives and developing value- Wiley and Sons, Inc., New York NY 10158-added livelihood schemes (Barber and rine ornamental fish industry, and practices 0012. Pratt 1997). sustainable fishing. Its fish collectors are Zerbe WB and CB Taylor. 1953. Seawater tem­ Cyanide detection tests (CDT). T h is themselves traders and exporters while perature and density reduction tables. Spec. getting higher prices for their products. Publ. No. 198, US Coast Geodetic Survey,computer-based test developed by IMA- 21 pp USA accurately detects cyanide in fish Australians are even better buyers than the ### tissues and organs. Managed by IMA and Americans. page 38

SEAFDEC Asian Aquaculture Vol. XXI No. 2 April 1999 37