Red flag grouper (Cephalopholis urodeta) care guide

Group
Marine fish
Other names
Flagtail grouper, V-tail grouper, Darkfin hind, Flagtail rockcod, Chevron rockcod, Duskyfin hind
Family
Serranidae (groupers and sea basses)
Origin
Mainly western Pacific (Ryukyus to the southern Great Barrier Reef, east to French Polynesia) plus Christmas Island; clear shallow reefs to 60 m.
Water
saltwater
Maximum size
28 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.020–1.025
Minimum tank
500 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
no

Care

Tank and decor: a fish-only system with caves and ledges. The tank size given is an estimate based on its adult size. Water: the sources give no species-specific figures, so the values here are general marine aquarium guidance: 24–27 °C, pH 8.1–8.4 and specific gravity 1.020–1.025. Keep nitrate low and the water well oxygenated. Behaviour: solitary and territorial; a male’s territory can contain up to six females. Identification: red-brown with a dark tail marked with pale V-shaped stripes. Very like C. miniata but with a dark tail fin. Name note: the Wikipedia list also gives this fish as "Cephalopholis urodelus", an old spelling of the same species. Trade and status: occasionally traded; too small for commercial fishing. IUCN: Least Concern. Indian Ocean fish are now treated as a separate species, C. nigripinnis. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Cephalopholisurodeta). Checked October 2026.

Diet

Mostly small fish (about two-thirds of its diet) plus crustaceans. Offer meaty marine foods such as fish, prawn, squid and mysis.

Breeding

Not described in detail. A male holds a territory with up to six females and courts them in the afternoon. It hybridises with C. nigripinnis at Christmas Island. Not bred in home aquaria.

Compatibility and tank mates

Not reef safe: it eats small fish and shrimps. Keep with fish too large to swallow.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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