Blueline demoiselle (Chrysiptera caeruleolineata) care guide

Group
Marine fish
Other names
Yellowfin demoiselle, Blueline damsel
Family
Pomacentridae (damselfishes)
Origin
Indian Ocean and western Pacific.
Water
saltwater
Maximum size
6 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
60 litres
Care level
intermediate
Temperament
peaceful
Reef safe
yes

Care

Tank: a reef aquarium with rockwork and caves. Tank: an estimated minimum of about 60 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: little is recorded in the sources. As a small Chrysiptera it is likely to be among the milder damsels. Identification: yellow with a blue line along the back. Up to 6 cm. Trade: IUCN: Least Concern. Not CITES-listed. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chrysipteracaeruleolineata). Checked October 2026.

Diet

A small omnivorous damsel. Offer small frozen foods such as mysis and brine shrimp, flake and algae-based food.

Breeding

The species article gives no breeding details. In the genus, pairs lay eggs on a hard surface and the male guards them.

Compatibility and tank mates

Reef safe. Best with other peaceful or small community fish.

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

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