Koran Angel (Pomacanthus semicirculatus) Care Guide
Pomacanthus semicirculatus, the semicircle or Koran angelfish, is a large Indo-West Pacific angel whose juveniles bear distinctive white half-circle markings.
Compiled by Aquairi from published sources · Published · Updated
Overview
Pomacanthus semicirculatus, the semicircle or Koran angelfish, is a large marine angel of the family Pomacanthidae. FishBase records a maximum length of about 40.0 cm standard length. Juveniles are dark with white half-circle patterns that transform as the fish matures.
Taxonomy
- Family: Pomacanthidae
- Genus: Pomacanthus
- Scientific name: Pomacanthus semicirculatus
Habitat
FishBase reports an Indo-West Pacific range from the Red Sea and East Africa to Samoa, north to southern Japan and south to Western Australia and New South Wales. It is marine, reef-associated and non-migratory; juveniles favour shallow protected areas while adults prefer coastal reefs with heavy coral growth, at depths of about 1-40 m.
Tank requirements
- Minimum tank volume: 1000 L (264 gal)
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- dKH (carbonate hardness): 8-12
- Lifespan: 15-25 years
Diet
FishBase reports that young specimens consume sponges, tunicates and algae. In aquaria a varied diet including sponge-based angelfish foods alongside marine algae and meaty foods is required, offered in frequent feedings.
Compatibility
This is a large, semi-aggressive angel. FishBase notes that it is generally solitary or in pairs. Suitable companions include tangs in large tanks, triggers and large wrasses, while small or timid fish may be intimidated.
Reef compatibility
Because it feeds on sponges and tunicates, the species is not considered reef-safe and may damage corals, sponges and tunicates. It is best kept in fish-only systems. Maintain specific gravity around 1.024-1.026 and carbonate hardness of 8-12 dKH.
Conservation status
IUCN Red List: Least Concern (assessed 2009), as reported by FishBase. FishBase notes low resilience with a population doubling time of about 4.5-14 years.
Koran Angel (Pomacanthus semicirculatus): Breeding Guide
Overview
Pomacanthus semicirculatus, the Koran or Semicircle angel, ranges across the Indo-West Pacific from the Red Sea and East Africa to Samoa, north to southern Japan and south to Western Australia. FishBase lists a maximum standard length of about 40 cm and a depth range of roughly 1 to 40 m.
Adults feed on sponges, tunicates and algae, so the species is not reef-safe. Juveniles inhabit shallow protected areas and carry the white half-circle markings that give the fish its common name, while adults prefer coastal reefs with heavy coral growth and are generally solitary or in pairs.
Sexing
Sexes cannot be told apart by external colour. The genus is generally protogynous, with females able to become males, so a pair is usually formed by growing two fish together and letting the dominant individual turn male.
Spawning Behavior & Trigger
Like other large Pomacanthus, this species is oviparous and spawns as pairs that rise off the reef to release eggs and sperm into the open water column. Fertilization is external and the gametes are carried away on the current.
Species-specific timing is not detailed in the consulted sources; related large angels spawn at dusk, so twilight is the expected trigger for pelagic spawning in this species.
Egg & Fry Care
The eggs are pelagic and float up into the plankton, hatching into minute larvae adapted to open-water drift. They require natural ocean micro-plankton during a prolonged larval phase.
FishBase notes that young of this species make excellent, hardy aquarium fish, but that refers to wild-caught juveniles; the consulted sources report no home-rearing of larvae from egg to settlement.
Common Challenges
- Pelagic eggs disperse in open water, so there is no nest or clutch to manage.
- Larvae need micro-plankton first foods that are not available in home systems.
- Adults reach about 40 cm and need very large tanks, complicating broodstock conditioning.