Indo-West Pacific: Philippines, eastern Indonesia and north-west Australia
Water
saltwater
Maximum size
10 cm
Temperature
24–28°C
pH
8.2–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
250 litres
Care level
expert
Temperament
peaceful
Reef safe
yes
Care
A close relative of the mandarinfish, covered in green-ringed dark spots. With the mandarinfish it is one of only two vertebrates known to get blue colour from a cellular pigment. It needs a large, mature reef tank with a strong copepod population. Its thick slime coat helps protect it against parasites and against more aggressive fish. Wikipedia recommends 24–28 °C and pH 8.2–8.4; the salinity given here is general marine aquarium guidance. Wikipedia gives a maximum of 7 cm; the list gives 10 cm. It is occasionally found in the aquarium trade. Minimum tank size of about 250 litres is our estimate from the adult size and habits, not a published figure. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Picturesquedragonet). Checked October 2026.
Diet
Often only eats live copepods and amphipods, which it picks from rock and sand through the day. Some individuals accept small frozen foods once settled.
Breeding
Breeding in home aquaria has not been reported in the sources used here.
Compatibility and tank mates
Peaceful and reef safe, and coexists well with other peaceful species. Avoid other copepod-eaters and keep only one male.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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