If you live near a body of water, you are in the enviable position of being able to observe firsthand the environments and habits of a variety of aquatic creatures. You're also free to do a good deal of experimentation, in terms of different species. You should consider modeling your aquarium after a particular habitat — for example, a rocky pool, a bog, or an eel grass bed. You might even consider using local substrates, rocks, and other natural items in your tanks. Pay particular attention to the light and temperature cycles of the area in which you live. By duplicating these in captivity, you will be able to provide a healthier environment for your pets, and you will also encourage breeding.
Why do the colors of temperate species of fish seem more subdued than those of tropical fish?
Although some temperate fish species do rival the colors of tropical fish, it is true that the most spectacularly colored animals are found in the warmer parts of the world. This is possibly because there is more diversity of species in the tropics, and the bright colors help males and females of the same species recognize each other.
Although the basics of maintaining a cold-water aquarium are similar to those of tropical aquariums, you do have to consider the effects of heat. Many animals from temperate regions are very sensitive to rising water temperatures and have various ways of escaping these temperatures in the summertime. In the close confines of an aquarium, your pets will be denied the option of seeking deeper water to cool off. You may, therefore, need to install a chiller to moderate the temperatures during the summertime. Fortunately a wide variety of small models are now marketed for use in home aquariums.