All fish / Callionymidae

Rosy dragonet

Synchiropus rosulentus

Also known as hawaiian flagfin dragonet, rosy dragonet, hawaiian dragonet, flagfin dragonet

A small, sand-coloured dragonet from Hawaii with rosy red and white mottling, and males carry a tall, decorated first dorsal fin that they raise when displaying. It lives on open sand and rubble, where its camouflage hides it well. Keepers of mature reef tanks and specialists in Hawaiian fishes value it for its quiet, constant grazing habits and the male's flag-like display.

Care at a glance

Care level

Hard

Temperament

Peaceful

Adult size

6 cm

Temperature

22 to 26 °C

pH

8.1 to 8.4

Smallest tank

150 litres

Keep as

Singly or as a male and female pair; never two males together

Diet

Carnivore: live copepods and amphipods grazed from rock and sand, plus frozen copepods, baby brine shrimp and finely chopped mysis once weaned

Swims

Bottom of the tank

Lifespan

2 to 5 years

Water

Marine (saltwater)

Wild range

Hawaiian Islands (endemic)

Breeding

Like other dragonets, the pair rises off the bottom at dusk and scatters buoyant eggs that drift as plankton. Spawning sometimes happens in aquariums, but raising the very small larvae needs tiny live foods such as rotifers and copepods and is rarely achieved.

Good to know

It is seldom traded and needs a well-established tank with a healthy population of copepods, as many specimens starve before they will take prepared foods. Males fight each other, and it should not be kept with dragonets or other fish that compete for copepods.