Bicolor parrotfish (Cetoscarus bicolor) care guide

Group
Marine fish
Other names
Bicolour parrotfish
Family
Scaridae (parrotfishes; now often placed in Labridae)
Origin
Indian Ocean and western Pacific, Japan to Australia; lagoons and seaward reefs at 1–30 m (recorded to 40 m).
Water
saltwater
Maximum size
76 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Care level
expert
Temperament
semi_aggressive
Reef safe
yes

Care

Juveniles (white with an orange-edged black spot on the dorsal fin) are sold, but adults reach about 76–80 cm. This fish is for public-aquarium-sized systems: it outgrows home aquaria and needs a very large volume of open swimming space, so no home tank size is given. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and salinity SG 1.023–1.026, with stable, well-oxygenated water. Males are territorial and defend feeding grounds on outer reefs. Juveniles shelter among dense coral and algae. The IUCN lists it as Least Concern; threats include coral bleaching, pollution and overfishing. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Cetoscarusbicolor). Checked October 2026.

Diet

A grazer that scrapes algae from rock and coral with its beak-like teeth. In captivity it needs constant grazing on algae and nori plus marine greens, spirulina foods and some meaty items, several times a day.

Breeding

A sequential hermaphrodite: fish start as females (initial phase) and later become males (terminal phase), maturing at about three years. Not bred in captivity.

Compatibility and tank mates

The list rates it reef safe, but in practice parrotfish rasp at rock and coral surfaces and adults can damage corals. Keep with large, robust fish.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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