Lake Malawi is the ninth biggest lake among all lakes around the world with an area of about 31 000 km². The lake is 585 km long and at the most about 87 km broad. The maximum depth is around 700 meter and the average depth is 273 m, the surface of the lake is 472 metres above the sea level. The lake is bordered by Tanzania, Moçambique and Malawi. This great lake belongs to the african great rift lakes, and it's one of the oldest lakes known. Under the very long period of time that the lake has been isolated from the other african lakes there had been developed more than 600 species that are endemic to the Lake Malawi. The species are specialized to exist in the many different habitats in the lake, the cichlids are in most cases also very brightly coloured. Malawi cichlids are among the most beautiful and interesting fishes that could be kept in an aquarium.