Spiny chromis (Acanthochromis polyacanthus) care guide

Group
Marine fish
Family
Pomacentridae (damselfishes and chromises)
Water
saltwater
Maximum size
14 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
250 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
yes

Care

This page is based on the list entry only; check details with your supplier. A chunky, dark chocolate-brown fish, slightly paler around the pectoral fins. The minimum tank size is an estimate; provide rockwork with caves. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and a specific gravity of 1.023–1.026. Keep nitrate low and water quality stable. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies). Checked October 2026.

Diet

Plankton-feeders: offer small meaty foods such as mysis, brine shrimp and copepods with quality flake or pellets, in small amounts two or three times a day.

Breeding

Not described in the list. Unlike most chromises and damsels, Acanthochromis polyacanthus is widely known for guarding its young after hatching rather than having drifting larvae.

Compatibility and tank mates

Listed as reef safe. Pairs and adults can become territorial, so give it space and choose robust tankmates.

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

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