Petrochromis Polyodon care guide

Petrochromis Polyodon (Petrochromis polyodon) — minimum tank 700 L, temperature 24-27 °C, pH 8.5-9.2.

Overview

Petrochromis polyodon is among the largest Petrochromis, reaching about 22 cm. The species is widely distributed in Lake Tanganyika across both rocky and intermediate habitats; the body is robust and slate-grey to bronze, with extensive blue iridescence on the head and fins in breeding males.

Taxonomy

Family: Cichlidae
Genus: Petrochromis
Scientific name: Petrochromis polyodon
Common synonyms: Texas Red

Habitat

Endemic to Lake Tanganyika, where it grazes the algal turf on rocky shores. Tanganyika water is hard and alkaline (pH 8.5-9.2, KH 12-20), with stable warm temperatures and very high dissolved oxygen. Petrochromis species are confined to specific stretches of shoreline and form large foraging groups over the upper rocky zone.

Tank requirements

Minimum tank volume: 700 L (184.9 US gal)
Adult size: 17-22 cm
Temperature: 24-27 °C (75-81 °F)
pH: 8.5-9.2
GH: 12-25 °dGH
Water flow: medium
Lifespan: 10-15 years
School size: ≥6 individuals

Diet

A strict aufwuchs grazer with tightly packed comb-like teeth used to scrape biofilm from the rocks. In aquaria a vegetable-rich diet of spirulina pellets and blanched vegetables is essential; protein-heavy diets cause severe bloat. Large adults consume substantial quantities of food.

Compatibility

Aggressive and territorial; demands very large tanks (500+ L) with extensive rockwork and a single-species colony or pairing with other large herbivorous Tanganyikans. Do not mix with smaller mbuna-style fish that cannot withstand the pressure; multiple males must each have enough rock territory.

Breeding

A polygamous maternal mouthbrooder. The male defends a small flat rock and entices females to spawn; the female holds eggs and wrigglers for about four weeks before releasing the fry, which already feed on aufwuchs.

Conservation status

IUCN Red List: see species page. Most Petrochromis are widely distributed within Lake Tanganyika and assessed as Least Concern; however, the genus is collected for the ornamental trade and shoreline-specific morphs are more vulnerable.