Q. I have three goldfish in my freshwater aquarium, and after reading a copy of this magazine, I am wondering if I should use water test kits. My fish have lived for two years now and the water seems fine to me. I am not sure if it is worth the money and trouble to test the water.

A. Your question requires a two-sided answer. On the one hand, I believe that it is important for any hobbyist to have the ability to check water quality. This is vital for the health of the fish. After all, one cannot tell much about water quality simply by looking at it. Test kits are necessary to determine just how good, or bad, the water quality really is.

On the other hand, in some special cases, there may be no real need to test the water. If the aquarist has a large enough tank with a limited number of fish and does not intend to increase that number, and if he or she feeds the fish sparingly and changes water regularly (in other words, uses excellent aquarium maintenance techniques), there is probably no need for doing water tests. I hesitate to say this because most hobbyists tend to maintain a higher biological load in their tanks than they realize, and regular use of test kits helps reveal problems with water quality that may not otherwise be immediately obvious.