Emperor angelfish (Pomacanthus imperator) care guide

Group
Marine fish
Family
Pomacanthidae (marine angelfishes)
Origin
Indo-Pacific, Red Sea to Hawaii and the Austral Islands; coral-rich reefs under ledges and in caves, 1–100 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 ledges to shelter under and plenty of open swimming space. 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. Forms pairs in the wild and usually dominates other angelfish in an aquarium. Juveniles and adults may clean parasites from larger fish. It makes a knocking sound when frightened. Adults are blue with fine yellow horizontal stripes, a dark blue mask across the eyes, a dark band behind the head and a yellow tail. Juveniles are dark blue with white and pale blue rings and change colour gradually as they grow. Popular with aquarists for its colours. The article describes populations as stable with no major threat; it gives no IUCN category. 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/Pomacanthusimperator). Checked October 2026.

Diet

Eats sponges, tunicates and other encrusting organisms in the wild. Feed a varied diet several times a day: angelfish preparations containing sponge, frozen mysis and krill, chopped seafood, 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. Forms pairs in the wild. 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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