All fish / Siganidae

Blue-Lined Rabbitfish

Siganus doliatus

Also known as barred rabbitfish, blue-lined rabbitfish, bluelined rabbitfish, barred spinefoot, blue lined foxface, doliatus rabbitfish, pencil-streaked rabbitfish, ヒフキアイゴ, baronang, 斑带蓝子鱼, 双带蓝子鱼

This rabbitfish has a pale, deep and laterally compressed body covered in fine wavy blue lines, with a yellow back half and two dark bars running through the eye and across the head. It is kept because it grazes nuisance algae, is hardy once settled, and brings a bright, calm presence to large reef or fish-only tanks.

Care at a glance

Care level

Moderate

Temperament

Semi

Adult size

20 cm

Temperature

24 to 28 °C

pH

8.1 to 8.4

Smallest tank

450 litres

Keep as

Singly or as a mated pair; avoid other rabbitfish unless the tank is very large

Diet

Herbivore: nori and other marine algae, spirulina and herbivore pellets or flakes, with some mysis

Swims

Middle of the tank

Lifespan

5 to 10 years

Water

Marine (saltwater)

Wild range

Western Pacific: eastern Indonesia, Philippines, New Guinea, northern Australia (Great Barrier Reef), Melanesia

Breeding

It scatters pelagic eggs in pairs or groups, usually timed to the lunar cycle. Spawning in home aquariums is very rare and rearing the tiny larvae has not been done reliably outside research settings.

Good to know

The dorsal, pelvic and anal fin spines are venomous and give a painful sting, so handle with care. It can nip soft and LPS corals and needs plenty of swimming room as it grows to around 25 cm in the wild.