Community tank

Community aquaria are tanks that are designed to contain more than one species of fish. Most commonly they include a variety of species that do not normally occur together in nature, for example angelfish from Brazil, swordtails from Mexico, and gouramis from South East Asia. The aim of such communities is to bring together fish that are compatible in temperament and water requirements, while using their different colours and behaviours to add interest and entertainment value.

Though not usually called community tanks, most marine aquaria fit into this category too, using fish from places as diverse as the Caribbean, Red Sea, and western Pacific Ocean.

Other aquarists prefer communities, called biotopes, that represent particular geographic locations, and combine fish with appropriate decorative materials including endogenous rocks and plants. The most popular of these geographically correct community tanks are those replicating the cichlid habitat of the East African Rift lakes of Lake Tanganyika and Lake Malawi.

For freshwater community tanks, there are large numbers of species that make successful community fishes. Most of the livebearers, barbs, tetras, rasboras, danios, and rainbowfishes are peaceful, though a few species are fin nippers, most notably tiger barbs and serpae tetras. Angelfishes, gouramis, and Corydoras catfishes are also popular, though angelfish are predatory and will eat very small fish such as neon tetras and livebearer fry. If neon tetras are kept around fish unlikely to take advantage of their small size, they are very peaceful towards other fish.

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Wikipedia