Koran angelfish (Pomacanthus semicirculatus) care guide

Group
Marine fish
Other names
Semicircled angelfish, Half-circled angelfish, Zebra angelfish
Family
Pomacanthidae (marine angelfishes)
Origin
Indo-West Pacific, Red Sea and East Africa to Fiji, Samoa, southern Japan and Australia; sheltered coastal coral reefs, 1–40 m
Water
saltwater
Maximum size
40 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.020–1.025
Minimum tank
1000 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
no

Care

Needs a large tank with caves and overhangs and open swimming room. The minimum tank size of about 1000 litres is our own estimate from the adult size and habits, not a figure from the sources. No species-specific water figures are given in the sources, so the values here are general marine aquarium guidance rather than figures for this fish: 24–27 °C, pH 8.1–8.4 and a specific gravity of 1.020–1.025 (a fish-only system suits it). Keep conditions stable, with low nitrate and good oxygenation. Usually alone or in pairs. Juveniles are timid; adults become confident and can be territorial. Adults are grey-green at the front shading to dark blue at the rear, covered in small dark spots, with iridescent blue edges to the fins. Juveniles are dark blue with curved white and pale blue lines. Regularly traded. IUCN: Least Concern. 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/Pomacanthussemicirculatus). Checked October 2026.

Diet

Eats algae, tunicates and sponges. Feed a varied diet several times a day: angelfish foods with sponge, frozen mysis and krill, marine algae and spirulina.

Breeding

Marine angelfish are pelagic broadcast spawners: a pair rises into the water column, usually around dusk, and releases eggs and sperm together. Not bred in home aquaria.

Compatibility and tank mates

Not reef safe: it grazes sponges and tunicates and will pick at stony and soft corals, clam mantles and other sessile invertebrates. Best in a fish-only system with live rock. Keep one large angelfish per tank unless the system is very large; add it after more peaceful fish and alongside robust tankmates such as tangs, larger wrasses and triggerfish of similar size. Avoid small, slow or timid fish.

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

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