Koran Angelfish - Pomacanthus semicirculatus

Koran Angelfish (Pomacanthus semicirculatus)

The Koran Angelfish is a large and impressive marine angelfish known for the dramatic transformation it undergoes from juvenile to adult. Juveniles display dark blue to black colouration with curved white and blue bands, while adults develop a more subdued olive to brown body patterned with fine blue lines and vivid blue edging around the fins and face. Bold, intelligent and highly territorial once established, this species is best suited to large, mature marine aquariums with experienced care.

Common Name:
Koran Angelfish, Semicircle Angelfish

Scientific Name (Latin):
Pomacanthus semicirculatus

Maximum Size:
Approximately 40 cm

Water Type:
Marine

Origin / Natural Habitat:
The Koran Angelfish has a broad Indo-Pacific distribution and is associated with coral reefs, lagoons, channels and sheltered reef slopes.

Juveniles are often found in shallower protected reef habitats, while adults occupy more open coral-rich areas with caves, overhangs and substantial reef structure.

Water Parameters:
Temperature: 24–26°C
pH Range: 8.1–8.4
Salinity: SG 1.024–1.026
Nitrate: Low and stable
Ammonia/Nitrite: 0 ppm

Temperament:
Semi-Aggressive / Territorial

The Koran Angelfish is generally confident and can become strongly territorial as it matures.

It is usually best kept as the only large Pomacanthus angelfish unless the aquarium is exceptionally spacious and introductions are carefully managed.

Smaller or timid tankmates may be intimidated by a dominant adult.

Diet:
Omnivore / Sponge Feeder

The Koran Angelfish naturally feeds on sponges, tunicates, algae and other encrusting reef organisms.

In the aquarium, provide a varied diet including specialist marine angelfish foods containing sponge, quality marine pellets, spirulina, nori, frozen mysis, chopped prawn and other marine-based foods.

Several smaller meals throughout the day are preferable and help maintain healthy body condition and strong colouration.

Minimum Tank Size:
Approximately 700 litres

With an adult size of around 40 cm and a highly active, territorial nature, the Koran Angelfish requires a large aquarium with substantial horizontal swimming room and extensive rockwork.

Behaviour & Activity:
The Koran Angelfish is an active daytime swimmer that spends much of its time exploring rockwork and grazing reef surfaces.

Provide a combination of open swimming areas and large caves or overhangs where the fish can retreat.

Juveniles look dramatically different from adults and gradually transition from their bold curved stripe pattern into the finer-lined adult colouration as they mature.

Reef Safe:
With Caution

The Koran Angelfish should be considered reef safe with caution.

Its natural diet includes sponges and other encrusting organisms, and aquarium specimens may nip at fleshy LPS corals, soft corals, zoanthids and clam mantles.

Individual behaviour varies, but this species is not considered reliably safe for delicate coral displays.

Special Requirements or Care Notes:
Provide a large, mature marine aquarium with extensive live rock, caves and open swimming space.

A varied diet containing sponge-based foods is particularly important for long-term health.

Avoid keeping multiple large angelfish together unless the aquarium provides exceptional space and numerous visual barriers.

Strong filtration, good oxygenation and stable water chemistry are essential because this species becomes large and creates a significant biological load.

Careful acclimation and quarantine are recommended, as large marine angelfish can be susceptible to transport stress and external parasites.

This species should only be purchased with its substantial adult size and long-term space requirements fully considered.

Suitable for:
Experienced

Availability:
Regularly available

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.