Blue Devil Damsel

The Blue Devil Damsel is one of the most strikingly colored and widely available damselfish in the marine aquarium trade, renowned for its brilliant neon-blue coloration that makes it instantly recognizable. Males display an entirely electric blue body with a subtle orange or yellow tint at the tail, while females are often slightly duller with a clear or yellowish tail. This small but feisty fish is a member of the Chrysiptera genus, which contains some of the more manageable damselfish species, though the Blue Devil still earns its devilish name through persistent territorial behavior.

In the wild, Chrysiptera cyanea inhabits shallow coastal reefs and rubble zones throughout the Indo-Pacific, where it stakes out small territories among coral heads and rock crevices. It feeds opportunistically on algae, zooplankton, and small invertebrates, darting out from cover to snatch food before retreating to its defended territory. This territorial behavior translates directly to the aquarium, where the Blue Devil Damsel will aggressively defend its chosen area against fish of similar size and coloration.

Despite its aggressive temperament, the Blue Devil Damsel remains popular because of its extreme hardiness, brilliant color, and low price point. It is often used to cycle new aquariums, though this practice is increasingly discouraged in favor of fishless cycling methods. For best results, add this species last to a community tank to minimize territorial aggression, and provide plenty of rockwork with multiple hiding spots. A single specimen in a well-established reef aquarium can be a stunning addition, provided tankmates are chosen carefully to avoid bullying of more timid species.