Since there are over 20,000 species of fish that live under many differing environmental conditions, husbandry will vary depending on the natural environment for a particular species. Life-support systems must be set up and "acclimated" prior to receiving animals (Spotte 1979, 1981; Alabaster and Lloyd 1980; Hawkins and Lloyd 1981; Munro and Roberts 1989; Goodrich 1990). During construction, thought should be given to providing adequate space and water quality. If a municipal water supply is used the water must be either dechlorinated by aeration or by filtration through activatedcarbon or chlorine-precipitating compounds such as sodium thiosulfate. All water should be analyzed prior to use, whether municipal or well water. Investigators must be aware of the appropriate levels of pH, ammonia, nitrate, and calcium in the water medium (Tucker 1993).