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Emperor Angelfish

Pomacanthus imperator

Family: Pomacanthidae · Large Angelfish

Also known as: Imperator Angelfish, Imperial Angelfish

Max Size

15"

Min Tank

220 gal

Lifespan

15-20 years

Origin

Indo-Pacific, Red Sea

Diet

Omnivore

Swims

Middle

About

The Emperor Angelfish is arguably the most iconic and visually stunning large angelfish in the marine aquarium hobby. Adults display a breathtaking pattern of alternating horizontal yellow and blue stripes running across the body, a bold black mask edged in vivid blue across the eyes, and a bright yellow caudal fin. This striking livery has earned the Emperor Angelfish a place as one of the most recognized and sought-after reef fish in the world, gracing countless magazine covers and aquarium displays.

One of the most fascinating aspects of this species is its dramatic transformation from juvenile to adult coloration. Juvenile Emperor Angelfish are dark navy blue to black with concentric white and electric blue circular patterns, looking so different from adults that they were once classified as a separate species. This metamorphosis begins at around 3 to 5 inches and takes several months to complete, providing aquarists with a remarkable front-row seat to one of nature's most dramatic color changes. In the wild, juveniles serve as cleaner fish for larger species, picking parasites from willing hosts at cleaning stations on the reef.

Due to its large adult size of up to 15 inches and its need for open swimming space, the Emperor Angelfish requires a very large aquarium of at least 220 gallons. It is considered reef-compatible only with extreme caution, as it will readily nip at stony and soft coral polyps, sponges, and clam mantles. Most experienced aquarists house this species in fish-only or fish-only-with-live-rock systems. Despite its demanding requirements, a well-maintained Emperor Angelfish is an extraordinarily rewarding fish to keep, often developing a bold personality and becoming the undisputed showpiece of any large marine aquarium.

Feeding & Diet

Omnivore

Emperor Angelfish are omnivores that require a varied and nutritious diet. Offer high-quality angelfish preparations containing marine sponge, Spirulina-enriched flakes or pellets, frozen mysis shrimp, enriched brine shrimp, and finely chopped seafood. Supplement with nori seaweed sheets and fresh marine sponge when available. Juveniles benefit from more frequent feedings of protein-rich foods. Feed two to three times daily to maintain optimal health and coloration.

Compatibility

reef-cautionlarge-angelfish-territorialcommunity-compatiblecoral-nipperfish-only-preferred

Emperor Angelfish can be territorial toward other large angelfish and similarly shaped fish. Only one Pomacanthus species should be kept per tank unless the system is exceptionally large (300+ gallons). They generally coexist well with tangs, wrasses, triggerfish, and other robust community fish. Avoid housing with other large angelfish unless introduced simultaneously into a very large system.

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Breeding

Not bred in captivity

Emperor Angelfish are pelagic spawners that form pairs during spawning events at dusk, rising into the water column to release eggs and sperm. Captive breeding has not been achieved due to the extended oceanic larval phase and the very large adult size requiring enormous breeding systems. All specimens in the aquarium trade are wild-caught.