Blue Damsel

Chrysiptera cyanea

Also known as Blue Devil Damselfish, Blue Devil Damsel, Sapphire Devil

SaltwaterFish

Blue Damsel (Chrysiptera cyanea) — Brian Gratwicke · CC BY 2.0

Care at a glance

Temperature: 75–81°F (24–27°C)
pH: 8.1–8.4
Adult size: 3.1 in (8 cm)
Minimum tank: 29 gal (110 L)
Temperament: Aggressive
Social behavior: Social
Swim level: Middle
Difficulty: Beginner
Breeding: Medium
Rarity: Very common
Reef safe: Reef safe
Origin: Indo-Pacific
Family: Pomacentridae

Overview

Extremely hardy and cheap, which is why it is everywhere in the hobby, but its temperament is a real problem. A lone male will bully a peaceful community, so it is best added last or kept in a group of five to seven in a 55-gallon-plus tank to spread out the aggression. Technically reef safe because it ignores corals and inverts. Accepts almost any prepared or frozen food.

In the wild

Found across the tropical Indo-Pacific over shallow lagoon and reef-flat habitats with plenty of rubble and coral. It sticks close to the bottom third of the reef, using cracks and coral heads as cover. In captivity it needs a lot of rockwork and defined territories, otherwise its aggression has nowhere to diffuse.

Good to know

A Pomacentridae damsel. Males and females differ in color, and males in many populations develop an orange tail and face. It is a demersal spawner where the male guards eggs laid on a cleaned rock surface. Famous as one of the most aggressive small marine fish, males set up rigid territories and chase intruders relentlessly.

Did you know

It is one of the hardiest saltwater fish sold, which historically made it the go-to fish for cycling tanks, a practice now discouraged because the fish that survives the cycle is nearly impossible to catch out of the rockwork afterward.