Why Keep Marine Fish?
Guidelines and advice for keeping marine aquarium fish.
You've been bitten by the saltwater bug, haven't you? Every time you visit your dealer, you are captivated by the absolutely gorgeous saltwater fish and invertebrates on display. You've kept freshwater fish successfully for several years and, up until now, you've resisted the temptation to set up a saltwater tank.
And why not. Other hobbyists have related horror stories that have served to dampen your enthusiasm for the denizens of coral reefs. "They only live a few weeks," some say. "You've got to fuss with the tank every minute," others whine. "One little mistake, and everything in the tank is dead," a fellow hobbyist warns. "I gave up and went back to breeding Synodontis catfish. I wanted something easier."
You hear these conversations repeated in your head as you gaze into the dealer's tank. An exquisitely beautiful mandarin fish floats just above the bottom, propelled by the constant movement of its translucent blue fins. From underneath a rock nearby, a gaudy little neon goby peeks out. Pink anemones sway in the water currents. You can't resist any longer...you've got to set up a marine tank.
I will not add my voice to those who would discourage you. On the contrary, marine aquariums have given me tremendous pleasure for the past 20 years or so. However, I would discourage you from launching into the marine hobby without first giving some serious thought to the undertaking. A marine aquarium will require more of your time than a freshwater tank, but your time will be well rewarded. Provided, that is, you make an effort initially to learn about marine aquariums and to plan your marine tank carefully.
For starters, read a book. Magazine articles, such as this series, can help steer you in the right direction, but there is no substitute for extensive knowledge when it comes to marine aquarium keeping, and books are your best source of all the basic information in one convenient place. Titles you might consider include The Tetra Encyclopedia of the Marine Aquarium (Dick Mills, 1987, Tetra Press, Morris Plains, NJ, 208 pages) and The Marine Aquarium Handbook, Beginner to Breeder (Martin A. Moe, Jr., 1982, Green Turtle Publications, Plantation, FL, 170 pages).
If you think you might like to have a tank primarily for invertebrates, do not think that this can only be done with complex and expensive filtration and lighting systems. True, corals and some of the other choices for "reef tanks" are not for the beginner, but there are a host of invertebrate species that can be included in a simple, small and entertaining setup.
For ideas about setting up an invertebrate aquarium there are a number of books. These include The Marine Aquarium Reference, Systems and Invertebrates (Martin A. Moe, Jr., 1989, Green Turtle Publications, Plantation, FL, 510 pages), Small Reef Aquarium Basics (Albert Thiel, 1989, Aardvark Press, Bridgeport, CT, 170 pages) and The Reef Tank Owner's Manual (John Tullock, 1990, Aardvark Press, Bridgeport, CT, 272 pages).
As you read one (or preferably, all) of these books, make notes. Create a list of fish and/or invertebrate species that you think you might like to keep. Write down questions that arise and points about which you feel you need more information or a better explanation.
Also, decide how much money, space and time you can devote to your marine aquarium. In this way, you can develop a plan that will guide you when you begin purchasing equipment, and later as you acquire specimens. If you have a well thought out plan in hand before you actually begin, you will spare yourself some frustration, not to mention expense, as you proceed with the project. In developing your plan, keep the following five points in mind.
Number one, keep it simple.
As a novice, you should be paying more attention to maintaining good water quality, providing proper nutrition for your specimens and carrying out routine maintenance, and less attention to installing the latest piece of high-tech equipment. Make no mistake, none of the fancy equipment currently available will substitute for proper husbandry on the part of the aquarist. Start with a basic system and learn to maintain it properly. Then you will be better able to decide wisely if additional equipment will really help you get more enjoyment out of your tank. In future articles in this series, we will explore the proper utilization of specialized equipment.
Number two, keep it roomy.
Marine fishes require ample space. Even the largest aquarium is tiny in comparison to the vastness of the ocean around a coral reef. The size tank you choose will, most likely, be determined by the space and budget you have available. Therefore, if you only have room for a 10-gallon (38-liter) tank, don't set your heart on a fish that requires a 50-gallon (189-liter) tank. Plan to keep species that are in proportion to the size of the captive ocean you are contemplating.
Number three, keep it stable.
Apart from the abyssal depths of the ocean, the coral reef environment (from which comes virtually all of the fish and invertebrate species offered for sale in the aquarium trade) is among the most stable on earth. Reef fishes and invertebrates have therefore not evolved adaptive strategies to cope with rapid fluctuations in environmental conditions.
This is in marked contrast to freshwater fishes, which generally come from rivers, streams and lakes that may experience quite drastic changes throughout the course of a normal year. Maintaining stability in a marine tank means basically that you must have reliable equipment, and you must perform required maintenance consistently.
Number four, keep it clean.
Feed sparingly and remove dead organic matter promptly. Siphon out detritus on a regular basis. This chore is usually done in conjunction with removing water for a routine water change. Above all, do not allow pollutants to accumulate in the tank. Pollutants can be generated within the tank (compounds such as ammonia, nitrite and nitrate, about which we will have much to say in a future article), as well as from outside the tank (household chemicals, improperly used medications and additives, and sometimes pollutants in tap water).
One of the major physiological differences between marine fish and their freshwater counterparts is their relationship to the watery medium in which they live. In freshwater fishes, the body fluids are "saltier" than the water surrounding them. Freshwater fish constantly absorb water by osmosis, and are thus always in physiological danger of fluid overload. To compensate for this, freshwater fishes rarely drink water and their kidneys excrete copious quantities of very dilute urine to rid their bodies of the excess water.
Marine fishes, on the other hand, have body fluids that are less "salty" than the seawater surrounding them. Thus, they lose water to their surroundings and, ironically, are in constant danger of dehydration. To compensate, marine fishes drink large amounts of seawater and excrete relatively small amounts of concentrated urine.
In both marine or freshwater fishes, only water itself enters or leaves the tissues via osmosis. Substances in the water generally must enter the body via ingestion. Because they ingest water continually, marine fishes are therefore much more susceptible to poisoning from water-borne pollutants than freshwater fishes are. For example, copper is often used in freshwater tanks to control algae growth — at a concentration of about 1 part per million — and freshwater fishes are not affected by its presence. However, copper is toxic to most marine fishes at a concentration roughly three or four times lower than this.
Number 5, keep it natural.
Try to duplicate, as closely as possible, the conditions under which your marine specimens would live in nature. This means, basically, that you should endeavor to thoroughly investigate the requirements of any species in which you are interested before you purchase a specimen.
Your new marine aquarium has the potential to afford you years of enjoyment and satisfaction. By following the five simple rules I have outlined above, you can begin having fun, and not frustration, from the outset.
In order to obtain both equipment and specimens for your new marine tank, you will need to do some shopping. Visit every dealer in your area, but do not shop simply to locate the cheapest price, especially for fish. One dealer may have a particular piece of equipment on sale at a bargain price, and you have little to lose in taking advantage of such a special "deal." However, much of your long-term success with marine aquarium keeping will depend upon the quality of both information and livestock that your dealer provides, and this can vary quite widely. Here are some guidelines to help you in selecting a quality dealer for marine fish and invertebrates.
Look for a dealer that has a large number of tanks devoted to saltwater specimens in relation to the overall stock of fishes. (In some cities, there are dealers that sell only marines, but this is hardly the rule.) A large selection of saltwater specimens usually indicates that the dealer is doing a brisk saltwater business, which implies that many other customers have been satisfied with the quality of the service and specimens provided.
Examine closely the condition of the specimens in the dealer's tanks. Are they active, alert, undamaged and free from signs of disease? Apply the same criteria to marine fish that you would when seeking healthy freshwater specimens.
Note especially whether the dealer quarantines marine specimens for a period of time before offering them for sale, or if specimens that arrived last night are hustled out the door this morning. Remember that the bulk of marine specimens are caught in the wild. Capture and shipment, often for thousands of miles, are very stressful for fishes, and they need a period of rest and recovery before being netted again, dumped in a bag and sent home with a novice aquarist. Devoting tank space for quarantining fishes that the dealer has already paid for costs him or her considerable money. You can expect to pay more for the same specimen in such a store, but I promise, it will be worth it in the long run.
Visit the store when business is slow and ask questions. Tell the clerk that you are considering a saltwater tank for the first time and that you want to learn about the hobby before you begin. If all you receive in return is a sales pitch for a giant tank with a complex, expensive filtration system, leave at the first opportunity and find another store that demonstrates a sincere interest in your success with the marine hobby. Don't expect any dealer, however, to spend a lot of time with you when the store is packed with customers. Come back on another day.
When you visit a store for the first time, come prepared with a couple of questions for which, from your reading, you already know the correct answers. You can quickly determine whether this store has knowledgeable personnel and dispenses good advice. There are, of course, legitimate differences of opinion among experienced marine aquarists about certain aspects of aquarium keeping.
Nevertheless, there is, at least among most experts on the subject, practically universal agreement on a number of key points. If you read several books and magazine articles devoted to marine aquarium keeping, you will easily discover these. If the store you visit seems consistently to provide information that is at variance with accepted practices and common sense, find another store.
You will need to invest some time in locating a good dealer for marine specimens. Once you have made your choice, reward that store's efforts with your patronage.
The business of selling marine fishes is fraught with risk and difficulty and may not be particularly profitable in comparison to, for example, a dress shop. Any dealer who makes the effort to provide you with good-quality specimens, courteous service and sound advice deserves to remain in business. And he or she can only do so if you shop there.
In the next installment of this series, I will discuss the equipment needed to maintain marine organisms successfully in the aquarium. For now, read, plan, shop, ask questions and make notes. Patience at this stage will be amply rewarded.