Intermediate Emperor Angelfish – Pomacanthus imperator

Quarantine and Conditioning Started on 9/18 - Release Date: 10/8
If you wish to purchase this fish before the release date we will hold the fish for you. Let us know your desired ship date. If there is an issue during the Quarantine process, we will issue a refund.

The Emperor Angelfish (Pomacanthus imperator) undergoes one of the most dramatic color transformations among marine aquarium fishes. This specimen is in the intermediate or transitional stage, displaying characteristics of both juvenile and adult coloration. The remaining blue facial pattern and dark body coloration are gradually giving way to the brilliant yellow horizontal striping characteristic of an adult Emperor Angelfish.

FishBase reports that this transition generally occurs when P. imperator reaches approximately 8–12 cm (3.1–4.7 inches). Juveniles begin with a dark blue-black body patterned with curved white and blue lines, while adults develop closely spaced horizontal yellow stripes across a blue body, a dark eye mask edged in blue, and a pale snout. FishBase

The Emperor Angelfish has an extensive Indo-Pacific distribution, ranging from the Red Sea and East Africa eastward into the central Pacific, north to southern Japan and south to Australia and New Caledonia. The species is well documented throughout Indonesia, including Bali, Raja Ampat, Sulawesi, the Mentawai Islands and other regions. FishBase

Habitat changes somewhat as the fish matures. Juveniles tend to shelter beneath ledges and in holes around protected reef areas. Subadults move into reef-front holes and surge channels, while large adults inhabit ledges and caves associated with well-developed coral reefs. The species has been recorded from approximately 1–100 meters depth. FishBase

Emperor Angelfish feed naturally on sponges, tunicates and other encrusting organisms. Their specialized natural diet is an important consideration in aquarium husbandry and should be reflected in the variety of foods offered in captivity. FishBase

This specimen is from Indonesia and is offered as one of Dr. Mac’s Quarantined and Conditioned Fish.

Care Guide

Scientific Name: Pomacanthus imperator (Bloch, 1787)
Common Name: Emperor Angelfish
Life Stage: Intermediate / Transitional
Family: Pomacanthidae
Origin: Indonesia
Availability: Wild Collected – Conditioned & Quarantined
Care Level: Moderate to Advanced
Temperament: Semi-aggressive / territorial
Reef Compatibility: Reef compatible with caution
Minimum Aquarium Size: 220 gallons recommended for long-term adult care
Maximum Size: 40 cm standard length / approximately 15.7 inches FishBase
Diet: Omnivorous feeder with strong sponge and tunicate component
Temperature: 75–80°F
Specific Gravity: 1.023–1.026
pH: 8.1–8.4

Aquarium Requirements: Emperor Angelfish become large, active reef fishes and require substantial swimming room as adults. Provide a spacious aquarium with open swimming areas combined with extensive rockwork, caves and sheltered areas. Plan the aquarium around the fish's adult size, rather than the size of the intermediate specimen at purchase.

Temperament: Pomacanthus imperator can become territorial as it matures. Care should be taken when combining it with other large angelfish or fishes of similar shape and behavior, particularly when aquarium space is limited.

Reef Compatibility: Reef compatible with caution. Emperor Angelfish should not be considered reliably safe with all sessile invertebrates. Their natural feeding ecology includes sponges, tunicates and other encrusting organisms, so a mixed reef containing an Emperor Angelfish requires careful livestock selection and observation. FishBase

Diet and Feeding: Provide a varied marine diet with particular attention to foods formulated for marine angelfish that contain sponge material. Supplement with marine algae, mysis shrimp, finely chopped marine foods and other nutritionally varied preparations. FishBase documents sponges, tunicates and other encrusting organisms as important natural foods. FishBase

Color Transition: This fish is being sold specifically in its intermediate stage. The transitional pattern is temporary and will continue changing as the fish matures. FishBase places the juvenile-to-adult transformation at approximately 8–12 cm. FishBase

Adult Size: FishBase records a maximum of 40 cm standard length, so this species should not be selected based on its relatively modest size during the juvenile or intermediate stages.