Petrotilapia nigra

Petrotilapia nigra is a large, impressive mbuna from Lake Malawi notable for the unusually dark, near-black colouration that fully dominant males develop, in contrast to the blue tones typical of the genus. Subdominant males and females are brown-grey. Like all Petrotilapia, P. nigra possesses specialised tricuspid teeth suited for scraping dense algae (Aufwuchs) from rock surfaces — a dietary specialisation that makes animal protein feeding highly dangerous.

This species requires a spacious aquarium of at least 300 L with extensive rock structures, as it is both large and exceptionally territorial. Only one male should be housed per tank under typical conditions. Females are maternal mouthbrooders, incubating eggs and fry for approximately 21–28 days. Due to its size, aggression, and dietary demands, P. nigra is recommended for experienced Malawi cichlid keepers only. Water chemistry must faithfully replicate Lake Malawi conditions.

Water: 24–28°C, pH 7.8–8.5, hard (GH 10–25, KH 6–15); strong mechanical and biological filtration mandatory for this large species. Tank: 300 L minimum; massive rockwork; a single dominant male territory; remove any rival males immediately. Feeding: Exclusively algae-based — spirulina flake, algae wafers, blanched greens; animal protein is lethal risk for this genus. Breeding: Maternal mouthbrooder; female holds 21–28 days; isolate brooding female to a quiet 60–80 L tank. Compatibility: Large, aggressive mbuna only; not suitable with any peaceful or mid-sized cichlids.