Moorish Idol

Zanclus cornutus

Its trailing dorsal banner and bold bands made it a symbol of the reef. Notoriously difficult – a true expert's fish.

A peaceful saltwater fish that grows to 22 cm, lives in the middle of the tank and needs 24–27 °C, pH 8.0–8.4 and an aquarium of at least 500 L.

Care at a glance

Water

Saltwater

Temperature

24–27 °C (75–81 °F)

pH

8.0–8.4

Adult size

22 cm (8.7 in)

Aquarium

500 L or bigger (132 US gal)

Temperament

Peaceful

Group size

Fine on its own

Swims

Middle

Diet

Omnivore

Wild home

Tropical Indo-Pacific

Good to know

• Delicate. Sensitive to poor water quality.
• Coral nipper. Picks at corals, so it is no friend of a reef tank.

Tank mates

Good company: Blue-Leg Hermit Crab, Copperband Butterflyfish, Firefish Goby, Foxface Rabbitfish, Mandarin Dragonet, Neon Goby, Regal Angelfish, Skunk Cleaner Shrimp, Snowflake Moray, Wrought Iron Butterflyfish.

Attacked by: Clown Triggerfish.

Eats the newborn fry of: Harlequin Shrimp, Neon Goby.

Colours

• Classic epic

The care values are the ones Aquarius uses, based on how these animals live. Tank mates follow the game's rules: water type, temperature and pH, who can swallow whom, fin nipping, temperament and territory.