Mandarinfish (Synchiropus splendidus) care guide

Group
Marine fish
Other names
Mandarin goby, Green mandarin, Striped mandarinfish, Striped dragonet, Green dragonet, Psychedelic mandarinfish
Family
Callionymidae (dragonets)
Origin
Western Pacific, Ryukyu Islands to Australia; sheltered lagoons and inshore reefs
Water
saltwater
Maximum size
6 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
300 litres
Care level
expert
Temperament
peaceful
Reef safe
yes

Care

A small, slow, bottom-living dragonet with vivid blue, orange and green patterning. It has no scales but a protective slime coat, which may taste bitter to predators. Its feeding habits make it hard to keep. It needs a large, mature reef tank with plenty of live rock and a thriving population of copepods and amphipods (a refugium helps); a newly set-up tank will starve it. Fish that do learn to take prepared foods are hardy and resist diseases such as marine whitespot. Males have a taller, elongated first dorsal fin. It is listed as Least Concern by the IUCN. Water figures here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4, salinity SG 1.023–1.026. Minimum tank size of about 300 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/Synchiropussplendidus). Checked October 2026.

Diet

Picks tiny invertebrates off the rocks all day: wild fish have been found with harpacticoid copepods, polychaete worms, tiny snails, amphipods, fish eggs and ostracods in their guts. Many refuse anything but live copepods and amphipods; some can be weaned onto frozen foods.

Breeding

Not described in the source article. Mandarinfish are pelagic spawners that pair up at dusk; captive breeding is possible but specialist.

Compatibility and tank mates

Peaceful and reef safe. Avoid tankmates that compete for copepods (other dragonets, many wrasses) or bully slow feeders. Two males will fight; a pair can work in a large tank.

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

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