Central Indo-Pacific from the Cocos (Keeling) Islands to the Tuamotus and north to Japan; coral-rich reefs and current-swept channels to 20 m.
Water
saltwater
Maximum size
15 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
300 litres
Care level
intermediate
Temperament
peaceful
Reef safe
no
Care
Rarely imported but considered hardy. 300 litres is an estimate from its size. 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. Lives singly or in pairs and roams rather than holding a territory; it wedges into crevices when threatened and turns pale at night. Silver with two dark saddles, a dark eye bar and yellow rear fins. The IUCN lists it as Least Concern. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Chaetodonulietensis). Checked October 2026.
Diet
An opportunist that mainly eats microscopic algae, plankton and small attached invertebrates. In captivity it accepts most frozen and dry foods.
Breeding
Not described in the sources.
Compatibility and tank mates
Peaceful. The list rates it not reef safe, though Wikipedia notes it rarely eats ornamental corals and can clear Aiptasia and Majano anemones within about two to six weeks.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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