Yellowback fusilier (Caesio xanthonota) care guide

Group
Marine fish
Family
Caesionidae (fusiliers); now often placed in Lutjanidae
Water
saltwater
Maximum size
38 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Care level
intermediate
Temperament
peaceful
Reef safe
no

Care

Tank and decor: at 38 cm adult length and as an open-water schooling fish, this species outgrows home aquaria and is for public-aquarium-sized systems. Small juveniles are often sold; buyers should not expect to keep the adult in a home tank. Water: our 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 nitrate low and the water well oxygenated. Identification: a streamlined blue fusilier with a yellow back. It lives in large, constantly swimming schools and does poorly kept singly. The list gives a maximum size of 38 cm and rates it not reef safe. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies). Checked October 2026.

Diet

Feeds on zooplankton in open water. In captivity it needs several small meals a day of mysis, krill, enriched brine shrimp and fine marine pellets.

Breeding

Our sources for this page do not describe breeding. Fishes of this kind spawn in open water and are not bred in home aquaria.

Compatibility and tank mates

The list rates it not reef safe. It is peaceful towards other fish but very small shrimps may be eaten. It needs a school of its own kind and plenty of open water.

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

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