Western central Pacific, recorded from the Great Barrier Reef and Papua New Guinea; crevices, overhangs and ledges.
Water
saltwater
Maximum size
7 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 and decor: rockwork with caves and overhangs. The tank size given is an estimate based on its adult size. Water: the sources give no species-specific figures, so the values here are general marine aquarium guidance: 24–27 °C, pH 8.1–8.4 and specific gravity 1.023–1.026. Keep nitrate low and the water well oxygenated. Behaviour: lives in small groups and often swims upside down under ledges. Identification: bright lemon yellow with peach edging on the dorsal fin and around the eye. The list gives 7 cm; the article gives about 5.5 cm. Status: occasionally in the aquarium trade. IUCN: Least Concern. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Assessorflavissimus). Checked October 2026.
Diet
Plankton feeder. Offer frozen mysis, copepods and other small meaty foods several times a day.
Breeding
The male carries the eggs in his mouth (mouthbrooding).
Compatibility and tank mates
Reef safe and peaceful. Suits a community of small, peaceful fish.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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