Aquarium temperature

Most aquariums are tropical freshwater aquariums, where the water temperature is kept constant between 22 to 28°C. Temperatures above 28°C are generally found mostly only in aquariums with extremely heat-loving fish such as discus fish or armor catfish. Temperature variations (if any) are limited to a day-night rhythm, or a slight increase or decrease in temperature at spawning time.

There is no exact temperature limit for the water in the cold water aquariums. Quite often these aquariums do not have a heater and the water is generally kept at room temperature. Depending on the location of the aquarium it may even be necessary to use a refrigeration or space cooling device, making sure that on hot summer days the water temperature does not rise above a tolerable level for animals kept in it.

Larger fluctuations in temperature throughout the year are characteristic of conventional cold-water aquariums. The species frequently kept in them are those that are at home in the waters of Central Europe. These are, for example, orfen, moderlieschen, catfish, muhlkoppe and the three-spined stickleback.

Even the goldfish and the scheibenbarsch, natives of North America, are among the fish who do well at not too high of temperatures. In the last few years an increasing number of fish from the subtropical and tropical regions of elevated topography have found entry into the coldwater aquariums. These include fish such as gobies and various goodeidae.