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Aggressive within the group; keep with peaceful, large fish in a big rocky tank.
33 species in our list are a good match.
Aggressive within the group; keep with peaceful, large fish in a big rocky tank.
Spirulina-based pellets and vegetable matter; avoid rich foods.
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Common problems. Tap one to see the signs. This is a guide, not a diagnosis.
Maternal mouthbrooder (colony) · Hard
Maternal mouthbrooder; females hold small broods for about 4 weeks.
Keep a colony of 12 or more of one colour variant; males squabble constantly and need many females to spread aggression.
300+ L rockwork tank with caves, hard alkaline water (pH 8-9), moderate flow and very clean water; do not mix variants or other species.
Stable water, large weekly water changes, a vegetable-based diet and a large colony; females hold when they feel secure.
5-12 large eggs per spawn, held for about 4 weeks.
The female releases 5-12 large fry after about 4 weeks. Feed crushed spirulina flake and newly hatched brine shrimp; remove the female to a quiet tank if she is harassed.
Described by Poll in 1948 and named after British ichthyologist Ethelwynn Trewavas (1900-1993), this shy Lake Tanganyika cichlid lives in groups on shallow rocks in the southwest of the lake, grazing algae with a long gut suited to a plant diet.
Poll described this species in 1948, honouring Ethelwynn Trewavas. Petrochromis are large algae grazers with many small teeth. Males show a long, flowing tail.
First described by Max Poll in 1948. Named for Named after British ichthyologist Ethelwynn Trewavas.
11 facts checked with sources
Valid name; author Poll, 1948. Wikipedia lists 'Petrochromis trewavasae trewavasae Poll, 1948' as a synonym: the old subspecies split is no longer used. Fish sold as 'P. trewavasae ephippium' may now be treated as a separate species (P. ephippium appears as a name on tanganyika.si locality pages), but this was not confirmed from a primary source.
FishBase: Petrochromis trewavasae summaryNew value (legacy had no family). Tribe Tropheini.
FishBase: Petrochromis trewavasae summaryFishBase 18 cm TL. Legacy 20 cm slightly high.
FishBase: Petrochromis trewavasae summary · Wikipedia: Petrochromis trewavasae (cites FishBase, IUCN, ETYFish Project)Only FishBase found (Seriously Fish page could not be fetched). Legacy 24-27 is warmer than FishBase's range.
FishBase: Petrochromis trewavasae summaryFishBase only. Legacy 8-9 overlaps but runs higher; Lake Tanganyika cichlids are usually kept at pH 8-9, so treat this as a single-source figure.
FishBase: Petrochromis trewavasae summaryFishBase gives only a lower bound of 10 dH, no upper limit; not enough for a range.
FishBase: Petrochromis trewavasae summaryFishBase says it lives in groups in the wild but gives no aquarium number.
FishBase: Petrochromis trewavasae summaryFishBase describes wild fish as extremely shy; no fetched source describes aquarium aggression. Legacy 'aggressive' (a) is not confirmed.
FishBase: Petrochromis trewavasae summaryGrazes algae on rocks in shallow water; no source states a tank zone.
FishBase: Petrochromis trewavasae summaryNew value (legacy had none).
FishBase: Petrochromis trewavasae summaryLegacy 'big algae-eating cichlid' is right about diet. IUCN Least Concern (27 Feb 2025, per FishBase). A long gut means meaty foods are risky for Petrochromis (common hobby advice, not sourced here).
Wikipedia: Petrochromis trewavasae (cites FishBase, IUCN, ETYFish Project) · FishBase: Petrochromis trewavasae summary