Black and white chromis (Chromis margaritifer) care guide

Group
Marine fish
Other names
Bicolor chromis, Half-black chromis
Family
Pomacentridae (damselfishes)
Origin
Tropical central Indo-Pacific, out to the oceanic islands of the central Pacific; coral reefs.
Water
saltwater
Maximum size
7.6 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
100 litres
Care level
beginner
Temperament
peaceful
Reef safe
yes

Care

Tank: a reef or fish-only aquarium with open swimming space above live rock and caves for shelter. Tank: an estimated minimum of about 100 litres (our estimate from the adult size and habits, not a figure from the sources), more for a small group. Water: the sources give no species-specific figures, so the values here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and specific gravity 1.023–1.026. Keep conditions stable with good filtration and regular water changes. Behaviour: a small, active chromis that spends much of its time in the water column. Compared with most damselfish it is mild, though individuals may squabble among themselves. Identification: the front of the body is dark and the rear and tail are white, similar to the half-and-half chromis but with more black. The list gives a maximum of about 7.6 cm; the species article gives 9 cm. The article treats Chromis margaritifer as a former name, so it may be traded under a newer genus name. Trade: the article cites an IUCN assessment without stating the category. Not CITES-listed. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chromismargaritifer). Checked October 2026.

Diet

A plankton-feeding omnivore. Offer several small meals a day of frozen mysis and brine shrimp, finely chopped seafood, quality flake and small pellets, with some marine algae-based food.

Breeding

The species article gives no breeding details. Like other chromis it is an egg-layer, with the male guarding eggs on a hard surface, but captive breeding is rarely reported.

Compatibility and tank mates

Reef safe: leaves corals and invertebrates alone. Suits community reef tanks with other peaceful to moderately assertive fish. Avoid large predators that could swallow it.

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

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