All fish / Pomacentridae

Longfin Damselfish

Stegastes diencaeus

Also known as longfin damsel, longfin damselfish, honey damsel, yellow damsel, caribbean longfin damsel, 长鳍真雀鲷

Juveniles are bright yellow with thin blue lines on the head and back and a dark spot near the dorsal fin, and the long, pointed fins give the species its name. Adults turn dark brown to blackish. It is tough and cheap, so people sometimes buy it for new reef or fish-only tanks.

Care at a glance

Care level

Easy

Temperament

Aggressive

Adult size

11 cm

Temperature

24 to 28 °C

pH

8.1 to 8.4

Smallest tank

200 litres

Keep as

Keep singly

Diet

Omnivore: algae, marine flake, pellets, mysis and brine shrimp

Swims

Bottom of the tank

Lifespan

5 to 10 years

Water

Marine (saltwater)

Wild range

Western Atlantic: Florida, Bahamas, Caribbean Sea

Breeding

The male guards an algae patch and a nest where the female lays sticky eggs, and he fans and defends them until they hatch. Spawning can happen in large tanks, but raising the tiny pelagic larvae is hard and rarely managed at home.

Good to know

It becomes very territorial with age and will attack fish much larger than itself, so add it last and give it plenty of rockwork. The juveniles look a lot like the beaugregory and cocoa damsels.