Emperor angelfish is probably one of the most prominent angelfish in the aquarium trade. It is both vibrantly colored and graceful and is often referred to as the ‘Crowning jewel’ of the aquarium. Because of its bright coloration, mostly aquarists shortlist this fish for their aquariums. It is a favorite among nature photographers as well.  Although emperor angelfish is fairly hardy, it should only be kept under the supervision of experienced fish keepers due to their strict water parameters and tank size requirements.

Whilst this fish is well recognized and very popular, it comes with a comparatively high price tag as well. Moreover, caring for emperor angelfish requires a good understanding of the basic needs of this fish. This post has the basics of Emperor Angelfish care to make you ready to own one

Emperor Angelfish – Overview

Common Name

The common name of this fish is emperor angelfish and also called Imperator Angelfish.

Scientific Name

The scientific name of emperor angelfish is Pomacanthus imperator.

Habitat or Origin

The emperor angelfish is a reef-associated species that is native to the Pacific and Indian Oceans. It lives in the areas of the Red Sea to Hawaii and the Austral Islands. This fish lives in either rocky habitat or outer coral reef at depths of around 5–60 m.

Average Size

In the wildlife, Emperor angelfish can easily reach a length of up to 15 inches. However, it is unusual for the fish in an aquarium to grow this long due to space issues. Most of the fish in the aquarium will grow to a maximum length of 12 inches.


Emperor angelfish transforms its appearance through different phases of its life (juvenile, sub-adult, and adult). In all of these phases, it undergoes drastic changes in its appearance.

Juveniles have a black-colored body covered with C-shaped bands. They usually have three thick white bands. Sapphire blue bands separate these white ones.

In the sub-adult phase of life, their appearance starts transforming into that of a fully matured adult.

Adults have yellow and blue horizontal stripes on their bodies.

The fins of both juveniles and adults are rounded and well blended within the fish body to create a uniform shape. Because of their unique appearance, Emperor angelfish is a vivid addition to your aquarium.

Life Span

The average life span of this fish is more than 20 years (yes you heard it right). Emperor angelfish is very sensitive to water parameters and is prone to getting different diseases if tank conditions are not up to the mark. To avoid this and give them a longer than expected lifespan, you have to diligently work to meet their needs.


Emperor angelfish is omnivorous in nature. It, sometimes, eats plant-based foods. But most of the time, it hunts for prey like crustaceans, larvae, insects, and the rest of the meaty foods. If you want your emperor anglerfish to truly thrive, make sure that you recreate a protein-rich diet as much as possible in the tank. When it comes to protein intake, chopped scallop, shrimp, and little pieces of squid are emperor fish’s favorite. For plant-based foods, you can go for either marine algae or spinach. You can also feed your emperor angelfish with vegetables like blanched peas, zucchini, small portions of shredded lettuce, and cucumber.

Gender Identification

It is very difficult to identify the gender; only when we have 2 Adults we can attempt, as Males are a bit larger and the coloration behind the eye is much darker in males.


Emperor angelfish has a semi-aggressive nature. So, you have to be extra careful in the selection of their tank mates.


Tang fish species are also one of the favorite tank mates. You can choose to keep a bonded pair of Emperor angelfish in a tank. Even a trio of one male and two females is also fine. But avoid placing two males together in a tank
Ideal Tank Conditions If you are keeping juveniles in your aquarium, the recommended tank size is at least 125 gallons. If you plan on keeping an adult or a pair of them, increase that size up to at least 180 gallons. Adult fish will need even more space. Fully-grown fish are supposed to live in tanks with no less than 220 gallons. As usual, if you provide them with an even larger space, this fish will be even happier.

Water Parameters

Ideal pH should be 8.1-8.4 and remember they are very sensitive to fluctuations in water parameters.


Breeding emperor angelfish is pretty difficult when they are kept in a tank. They require a large space to breed successfully. Most of the aquarists do not have an aquarium with a space large enough to encourage spawning with this fish. Their breeding is quite easy in massive environments like open oceans but almost impossible in a tank environment. They have a spawning mode of reproduction.

When they get ready to spawn, both females and Male rise closer to the water surface. The female distributes her eggs which drift to safety. A much larger space is required for this process which is rarely available in an aquarium.

Common Diseases

Unfortunately, they are prone to developing several diseases. The Emperor angelfish are at high risk of experiencing these common diseases: Marine Velvet, Ich, and Head and Lateral Line Erosion Disease.

Approximate Cost

Depending on the size, you would be able to own one of them between 125$ to 225$ in the USA.

What to look at when buying

Look for any white spots, torn fins, wounds near the mouth stay away from buying them. Buy the one which is active in the store.

Species in the Market

Queen angelfish, Semicircle angelfish, Regal angelfish.