White-cheek Tang (Acanthurus japonicus) Care Guide
Acanthurus japonicus is an Indo-West Pacific surgeonfish with a white face band and orange dorsal stripe, grazing algae on clear lagoon and seaward reefs.
Compiled by Aquairi from published sources · Published · Updated
Overview
Acanthurus japonicus, the white-cheek or white-faced surgeonfish, is an Indo-West Pacific tang of the family Acanthuridae. It has a dark body, a distinctive white band from the lower eye to the upper lip, a bright orange band in the soft dorsal fin, a yellow caudal peduncle shading to black, and yellow pectoral fin bases.
Taxonomy
- Family: Acanthuridae
- Genus: Acanthurus
- Scientific name: Acanthurus japonicus
Habitat
The species occurs in the Indo-West Pacific from Sulawesi (Indonesia) to the Philippines and the Ryukyu Islands. It is reef-associated, found in clear lagoon and seaward reefs, usually in shallow exposed areas at depths of 1-20 m, typically 5-15 m.
Tank requirements
- Minimum tank volume: 600 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Specific gravity: 1.024-1.026
- Carbonate hardness (dKH): 8-12
- Water flow: high
- Adult size: up to about 23 cm
- Lifespan: 10-25 years
Diet
This is a herbivore that feeds on algae. In the aquarium it requires plentiful algae or dried marine algae offered several times daily.
Compatibility
Semi-aggressive, especially toward other tangs. It can be kept with wrasses, clownfish, angelfish and sturdy triggers. Other tangs, particularly those of similar shape, should be avoided in smaller tanks. It occurs in small to large aggregations and is sometimes solitary in the wild.
Reef compatibility
The white-cheek tang is reef-safe and grazes algae. It needs a spacious reef aquarium with strong flow.
Conservation status
IUCN Red List: Least Concern.
White-cheek Tang (Acanthurus japonicus): Breeding Guide
Overview
Acanthurus japonicus, the White-cheek Tang, is a Western Pacific surgeonfish recorded from Sulawesi and the Philippines north to the Ryukyu Islands. FishBase lists a maximum total length of about 23 cm, with most individuals seen between 5 and 15 m on clear lagoon and seaward reefs. Like all members of the genus, it carries a single retractable spine on each side of the caudal peduncle.
It occurs solitarily or in small to large feeding aggregations and grazes filamentous algae. There are no documented cases of this species being spawned and raised through to settlement in a private aquarium.
Spawning Behavior & Trigger
Surgeonfishes of the genus Acanthurus are pelagic broadcast spawners. Spawning typically occurs at dusk in brief pair- or group-spawning ascents into the water column, often concentrated around the outer edge of fringing reefs or near reef passages. Many species gather to spawn when water warms, frequently around the full and new moon, with tidal currents helping carry the gametes off the reef.
Fertilization is external: males and females release sperm and eggs into open water during a rapid upward rush. Species-specific spawning data for A. japonicus has not been published in the consulted sources, so the description here reflects the general Acanthurus pattern.
Egg & Fry Care
Eggs and larvae are pelagic. The fertilized eggs float and hatch into transparent, scaleless acronurus larvae that are well adapted to open-ocean life and may remain in the plankton for more than 39 days before settling onto a reef.
This long planktonic phase, combined with the larvae's reliance on natural ocean micro-plankton, is why home rearing is not achievable. Only research aquaculture facilities have attempted larval rearing for any surgeonfish.
Common Challenges
- Gametes are scattered in open water, so no pair bond or nest forms that an aquarist could manage.
- Acronurus larvae require weeks of pelagic drift and specialized plankton not available in tanks.
- Adults reach over 20 cm and are semi-aggressive toward similarly shaped tangs, making conditioning a compatible pair impractical.