野岩丽鱼

Overview

Petrochromis famula is a specialized rock-grazing Tanganyikan cichlid. Managing it involves more than supplying algae-based food: aggression toward its own species and the demands of a heavily fed group require careful planning.

Distribution & habitat

Endemic to Lake Tanganyika, it occurs in the northern lake, usually over rocky bottoms in shallow water.

Aquarium setup

Build numerous rocky shelters with open swimming space between them. Sand is suitable for the base. These substantial, eager feeders impose a considerable waste load, making strong biological filtration essential. Retreats may still fail to protect subordinate fish, so be prepared to separate individuals.

Diet & feeding

Its natural food consists almost entirely of unicellular algae scraped from rocks. Thick lips and movable brushlike tooth pads form a specialized grazing surface. Use a high-fiber, low-protein diet dominated by vegetable foods, including spirulina flakes and softened greens. Small supplementary portions of brine shrimp, Daphnia, or bloodworms can add variety.

Behaviour & compatibility

Aggression falls mainly on conspecifics. Small or peaceful Tanganyikan fishes are poor companions. Denser stocking with robust fishes can sometimes spread aggression, but this approach depends on adequate space and filtration and never guarantees safety. Territorial males may persecute females severely enough to require separation.

Sexual dimorphism

Males are more colorful, with pointed dorsal, anal, and pelvic fins.

Breeding

Captive breeding is possible but challenging because of conspecific violence. A male claims an area and displays to females. During spawning the female releases eggs in batches and immediately gathers them. Approaching his anal-fin egg markings brings her into position to receive sperm. She then leaves his territory; he provides no brood care.

A brood may contain around 60 eggs. The female carries it for approximately four weeks while fasting. Minimize disturbance and provide separate accommodation when needed. Naturally released fry are about 1 cm long and accept suitably sized versions of adult foods; crush dry offerings and feed small portions several times daily.

Notes

The highly specialized grazing apparatus explains why acceptance of animal foods does not justify a meat-centered diet. Wild fish are not especially gregarious, so dense aquarium stocking used to manage aggression demands continued observation.