Sergeant major damsel

Care at a glance

The sergeant major is named for the five vertical black stripes on a yellow-white body, which resemble a military rank insignia. In the wild it swims in large schools above the reef, but in a tank it quickly takes charge of the place.

It is one of the cheapest and toughest saltwater fish to cycle a freshly set up tank with, but its territorial streak means it tolerates few other bold or territorial species alongside it. Add it as one of the last residents, not the first.

Good to know

• Territorial

Related species

• Lamarck’s angelfishGenicanthus lamarck
• Longhorn cowfishLactoria cornuta
• Banded pipefishDunckerocampus dactyliophorus
• Twinspot gobySignigobius biocellatus
• Humbug damselfishDascyllus aruanus
• Miniatus grouper (coral hind)Cephalopholis miniata