This assumption will be determined by the preferences of the closest to that fish you relative knows well. If the fish is an annual species of Africa or South America, try to keep it in the water in which you have had success with other fish of the same group. If it begins with a fish that does not know anything at all, try to find someone who can help you identify it. Generally speaking, all fish of South America live better in neutral waters to slightly acidic with a pH between 6.4 and 7.0 range, a temperature between 22 and 26 C and the most tender possible, without getting to use distilled or rain water. Fish of Central America seem to prefer harder, more alkaline, waters especially cichlids and viviparous. They need water with a pH between 7.0 and 7.8, and harder than usual. If your tap water is soft, add a small amount of non-ionized salts. Credit: Kevin Johnson-2011. Asian fish have the same requirements as the of South America, while the Australians have the same general requirements as those of Central America.
African fish can be categorized according to their habitat. The lacustrine fish require relatively hard, alkaline water while those of river require soft, acidic waters. Retailers in the industry they have economic kits for pH, hardness and thermometers. It may not raise fish, or even keep them without resorting to them. Another feature of water is its color. Many acuarofilos say have had great successes only using peat bog which acidifies the water and give it a dark brown colour at the same time. Others, however, say that it is not necessary to use peat bog to ensure life in aquariums. Original author and source of the article.