Blue damsel (Chrysiptera cyanea) care guide

Group
Marine fish
Other names
Orangetail damsel, Blue damselfish, Blue demoiselle, Blue devil, Sapphire devil, Sky-blue damsel, Cornflower sergeant-major, Hedley's damselfish, Red tail Australian damsel
Family
Pomacentridae (damselfishes)
Origin
Widespread in the Indo-West Pacific (not the Red Sea); reefs and lagoons.
Water
saltwater
Maximum size
8.5 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
75 litres
Care level
beginner
Temperament
aggressive
Reef safe
yes

Care

Tank: a reef or fish-only aquarium with rockwork and caves. Tank: an estimated minimum of about 75 litres (our estimate from the adult size and habits, not a figure from the sources). 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: very aggressive; a breeding pair will attack almost any similar-sized fish that comes near its territory. Identification: bright blue; males develop an orange tail, which signals breeding condition. Up to 8.5 cm. Trade: hardy and widely sold. A few were seen off Slovenia in 2013, probably released aquarium fish, so never release unwanted fish. IUCN: Least Concern. Not CITES-listed. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chrysipteracyanea). Checked October 2026.

Diet

In the wild it eats algae, tunicates and copepods. In aquaria offer flake, frozen mysis and brine shrimp and algae-based food.

Breeding

Pairs form to breed and the male guards and tends the eggs.

Compatibility and tank mates

Reef safe. Aggressive: keep one per tank, add it last, and avoid peaceful or small tankmates such as gobies and small wrasses.

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

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