Aquariums for Specific Situations
It is important to consider exactly what type of animals you wish to keep, and your reasons for doing so. The following discussion of aquariums designed for specific purposes, such as mixed-species aquariums, nursery aquariums, or quarantine aquariums, may help you in this regard.
One of the most fascinating aquarium types is that containing mixed species of fish or mixed species of invertebrates and fish. Often termed community aquariums, such displays can be both beautiful and interesting. The chance to observe the interactions of various groups of different creatures in a setting mimicking their natural habitat is one not to be missed. Unfortunately, many people do not realize that mixing various species complicates aquarium keeping. In no event should animals be selected for their looks or other desirable characteristics. Community aquariums should, ideally, be based on natural assemblages of animals and plants. It is important to consider such factors as territoriality and social structure when establishing such an aquarium. Also, you must realize that animals that coexist in the wild may not necessarily thrive together in captivity.
It is often a bad idea to house animals from different parts of the world in the same aquarium, even if they get along well, because one may be unusually susceptible to minor maladies of the other. Microorganisms that do no harm to an African fish may, for example, kill a related species from South America.
You must also consider the feeding methods of the creatures that you plan to keep together. For example, methodical, live-food specialists such as seahorses will starve to death in aquarium with more active fish, despite the fact that they may live together in peace. Similarly, filter feeders such as clams will need special attention in terms of diet and light in a community aquarium, even if other animals in the aquarium do not directly compete with them.
Although time-consuming and expensive to set up in the beginning, serious aquarists know the value of having a quarantine aquarium up and running at all times. Especially if you keep delicate, rare, or expensive creatures, you may wish to establish new animals in a separate tank before introducing them to the rest of your collection. The downside of this is that the newly arrived animal must endure two separate acclimatization periods. The stress of this can be lessened if the water chemistry of each aquarium is kept essentially the same.
Although some medications can be used in aquariums housing healthy animals, it is sometimes necessary to remove sick creatures to a separate aquarium to treat them for disease or parasites. Fish medications, especially those designed to kill parasites, will usually be fatal to any invertebrates that you may keep. Such medications may also kill the beneficial bacteria in the filters, resulting in a crash of the entire system.
It is often nearly impossible to raise baby fish in an aquarium containing adults. Of course, many fish parents protect their eggs and care for the young, but eventually the fry must live on their own. These tiny fish also require different types and quantities of food than do adults. It is therefore often easier to raise baby fish in a separate aquarium. Many young fish have incredibly large appetites and must be constantly surrounded by food that is easily located. In complex setups, they may not be able to obtain all the nourishment that they need. Many do well in fairly simple aquariums with bare bottoms, so that food can easily be found. This is especially true for those species that feed upon living animals like brine shrimp.
Most young fish are weak swimmers and would quickly be swept into the intake tubes of your main aquarium's filters. Sponge filters allow for effective filtration without posing a threat to tiny fish. Also, the outflow of water and air from the filter goes straight up, so that strong currents, which small fish cannot navigate, are avoided. Sponge filters are operated by simple air pumps, and gang valves can be installed to moderate the amount of air entering the filter.
Most growing fish require huge amounts of food. Baby seahorses, for example, may consume up to 3,000 individual brine shrimp each day. As newly hatched fish are often not very mobile, and are not adept at hunting, they must be literally surrounded by food if they are to thrive.
One of the most fascinating undertakings in aquarium keeping is to attempt to re-create a specific habitat within your tank. You might choose an area of particular interest, or a local habitat where you can actually collect what is needed to establish the environment in your aquarium. The list of possibilities is endless — African rift lakes, tidal pools in the northeastern United States, coral reefs in the Philippines. Any of these will provide lifelong opportunities for adventure and enjoyment.
Actually, nearly all animals will do better if they are housed in some approximation of their natural habitat. Some species will not survive at all unless they are kept in fairly natural situations. In attempting to re-create a specific habitat in your aquarium, research and planning is indispensable. Be sure to investigate not just the animals that interest you, but their entire environment as well. Learn all that you can about light cycles, temperature, and the plants and other creatures that influence the daily lives of your prospective pets. The learning process concerning such undertakings is ongoing and may lead you to the establishment of ever more complicated and fascinating habitats.
In the “Species Accounts” sections of this book (Chapters 7 and 10), you will find some discussion of creatures other than fish and the more traditionally kept invertebrates. Animals such as amphibians and freshwater insects are often well suited to aquariums that incorporate some areas of land in their design. You can easily create such setups using silicon and glass sheets to separate land and water areas. A number of aquariums that incorporate both land and water areas are also commercially available.
If you choose to establish an aqua-terrarium housing amphibians, be aware that frogs and salamanders are quite different creatures from fish. Although many species can be kept with fish, the sizes and temperaments of each must be carefully considered. Most fully aquatic amphibians, in contrast to their relatives, do not require live food but will feed upon commercially available pellets as well.
The amphibian most commonly kept with fish is the African clawed frog (
Most amphibians produce waste in a highly toxic form, so your filtration system must be carefully considered. Also, amphibians such as newts must be given a way to easily climb out of the water. Many are not as effective swimmers as fish and cannot tolerate strong currents. Finally, nearly all amphibians climb well and so must be housed in well-covered enclosures.
Even if you do not intend to house amphibians, you may still find the aqua-terrarium to be of interest. The establishment of a mangrove community within an aquarium offers the opportunity to keep one of the world's most unique fish, the mudskipper. Living in close association with the semiterrestrial mudskipper is a variety of other interesting fish and invertebrates, including fiddler crabs and archerfish. See the chapter on brackish aquariums (Chapter 14) for a more complete discussion of this fascinating habitat.
Trout holding tanks are large enclosures equipped with chillers and available from companies that supply trout farms and commercial fisheries. Although not specifically designed as aquariums per se, these enclosures can be quite useful to the serious hobbyist who has the space for a 4- to 6-foot tank. They are equipped with powerful pumps and allow for precise control of water temperature. Most are all plastic with a glass or acrylic front. Trout holding tanks are particularly useful for large, active fish, complicated aqua-terrariums, and for animals requiring cool temperatures.
