Convict Cichlid

Amatitlania nigrofasciata

Also known as: Zebra cichlid, Convict, Black convict

Water Parameters

• Temperature: 22–28°C
• pH: 6.5–8
• Hardness (GH): 89–322 ppm (5–18 dGH)

Values above are general hardness (GH). For carbonate hardness (KH), the buffer that keeps pH stable, see the water parameters guide.

Care Summary

The fish that teaches more people about cichlid behaviour than any other: cheap, indestructible, endlessly available, and sold as a hardy beginner cichlid, which is true right up until it pairs off and turns a community tank into a war zone. Named for the black bars on a steel-grey body, convicts are intelligent, characterful, and remarkable parents, and watching a pair raise and shepherd a cloud of fry is one of the classic experiences of the hobby. The catch is the aggression, which is serious and non-negotiable, and the breeding, which is so reliable that overpopulation and unwanted fry are perennial problems. Kept with clear eyes in an appropriate setup (a species tank, or a tough cichlid community) they are superb; kept by surprise in a peaceful community they are a disaster. Stated plainly, because the temperament is the whole story.

Tankmates

Hardy, fascinating, and a genuine handful: convict cichlids are small but pound-for-pound among the most aggressive fish in the hobby, especially once paired and breeding, when they commandeer most of a tank and attack anything that approaches. They are not community fish. The realistic options are a single fish, a bonded pair in a species tank, or a robust setup with other tough, similarly-sized cichlids and large armoured catfish that can stand their ground. They breed at the drop of a hat (the usual result of buying a male and female), producing diligent, ferociously-defended broods, so be ready for fry and the aggression that comes with them. They dig, rearrange, and uproot plants. Tolerant of hard Australian tap water.

Compatible with

• Common Pleco
• Synodontis Catfish
• Bristlenose Pleco

Avoid keeping with

• Betta
• Keyhole Cichlid
• German Blue Ram
• Angelfish
• Neon Tetra
• Guppy
• Cherry Shrimp

Common Problems

• serious territorial aggression, especially when breeding
• constant breeding and unwanted fry
• uprooting plants and rearranging decor
• incompatibility with peaceful community fish

Sources: seriouslyfish.com, fishbase.org · Last updated: 2026-06-20