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King Angelfish

The King Angelfish (Holacanthus passer) is a beautiful-colored, reef-dwelling fish with an elegant “crown” and was named for its regal appearance.

Its close relative, the Queen Angelfish (Holacanthus ciliaris) also has this crown feature but they vary slightly in size and overall coloration.

However, king angels may reach up to 14 inches long (35 cm), whereas queens can reach a whopping 18 inches in length.

In this article, we’ll discuss everything you need to know about king angelfish care, including diet, habitat, and tank mates.


Scientific NameHolacanthus passer.
Origintropical Eastern Pacific from the Sea of Cortez to Ecuador and Peru, including the Galapagos Islands.
AggressionLarge Aggressive – Predatory.
Minimum Tank Size100 gal (379 L).
Length14.0 inches (35.56 cm)
Aquarist Experience LevelBeginner.
Temperature66.0 to 81.0° F (18.9 to 27.2° C)
King Angelfish Characteristics

King Angelfish Origins & Habitat 

The king angelfish is a vibrant, reef-dwelling fish that is native to the eastern Pacific Ocean and Lower Gulf of California, Guadalupe Island, south in coastal waters to Peru, Cocos, and the Galapagos Islands.

The king angelfish prefer living in a rocky or coral reef environment. They can be found at all depths of the water column to a depth of 30 m (98.4 ft).

Also, they have been observed down to 80 m (262 ft). Tidepools are often where juvenile king angelfish may be found.

Life Cycle & Life Span/ Behavior


Eggs are pelagic and hatch within 60 hours after fertilization. After that, the fry is put into what’s called a “wiggler” stage, which lasts about 5 more days. 

During the wiggler stage, the fry will feed on their egg yolk until they’re free-swimmers. After about seven days, the fry starts getting hungry and will be very desperate for food.

Therefore, make sure to start feeding them after around seven days from hatching.


It takes up to two years for the juvenile king angelfish to become an adult.

During these 2 years, the juvenile lives alone hiding out in reefs or holes while growing larger and stronger before entering their next form of adulthood.


Once it gets into the adulthood stage, it becomes a little more confident and starts to take territories and brutally defend them against invaders

What Are the Features of King Angelfish?

Physical Appearance

The body shape of this species is oval like that of other angelfish types and is laterally compressed.

By nearly two-thirds of its length, the posterior tips of the dorsal and anal fins overlap the caudal fin in some specimens.

The mouth is tiny, and the snout is rounded. The Pomacanthidae family, which includes king angelfish, features a long and robust spine that extends from the lower cheek area.


1. Adults

Adults are generally a dark slate blue in color, however, you might find the rear margin of the scales is yellow or orange.

The bluish-colored margins of the dorsal and anal fins are highly apparent. The pectoral and caudal fins are golden yellow in color.

The gender of king angelfish may be distinguished by their color where males have white pelvic fins, while females have yellow pelvic fins.

A distinctive identifying feature of the species is a broad, white vertical line that begins at the rear edge of the pectoral fin and ends at the upper body margin.

2. Juveniles

Juveniles are more vibrant than adults, having multiple blue vertical stripes on the side of the body behind the white stripe and yellow to orange markings on the head. The forward one-fourth of the body is yellowish to orange in hue.

Length & Weight

King Angels are small reaching 14″ (35.6 cm) in length while the Queen can grow up to almost 18″ (45 cm).

Is King Angelfish Hardy?

The King Angelfish is a resilient fish that is suitable for novices. However, it is not suggested to acquire a young juvenile since they would have trouble adjusting to captivity.

King Angelfish Availability

King angelfish are frequently found in stores and online. The cost of a fish is dependent on its size, but the king angelfish are generally costly.

How to Care for King Angelfish?

Water Requirements

1. Water change

Although king angelfish are hardy fish, they are very sensitive to changes in water quality.

Ammonia spikes and nitrite levels should be kept at zero, and nitrate levels should be as low as possible. Therefore, A protein skimmer is highly recommended.

Also, water changes of up to 10% every two weeks are recommended for aquariums with more than 100 gallons.

To obtain the greatest results, water changes of around 30% should be done every three to four weeks in tanks with volumes greater than 250 gallons (940 l).

You can also use a suitable filtration system to remove impurities from your aquarium water.

2. pH Level

Improper ph level is one of the leading causes of death in king angelfish. A stable ph level is between 8.0 and 8.4.

You can help keep the ph level steady by using a high-quality water conditioner and doing frequent partial water changes.

3. Water Temperature

The king angelfish is frequently found in shallow water close to the bottom, where it can keep warm.

The ideal water temperature for king angelfish is between 66.0 to 81.0° F (18.9 to 27.2° C).

When the water temperature drops below 66 degrees, the king angelfish will become stressed and may stop eating and in severe situations when the water temperature drops too low, the fish will die.

To maintain a stable water temperature, you should use a high-quality aquarium heater. You should also place the aquarium heater in an area where it will not be disturbed by other objects in the tank.

Tank Setup

1. Size

A 100-gallon tank is required for an adult King Angelfish, however, 135 gallons or more is suggested for a community tank.

King angelfish are active swimmers and need plenty of space to move around so the larger the aquarium, the better.

2. Tank Decoration

King angelfish is a grazer and will benefit from having plenty of live rock with natural macroalgae growing on the surface, both initially for a new juvenile and over time.

Younger fish will require a lot of hiding places throughout the rock work as they mature, but other tankmates may use these hiding places when king angelfish youngsters become adolescents.

Also, it will be great if you add some driftwood and live plants to your aquarium.

3. Lighting

King Angelfish, like other fish from the family Pomacentridae, require a high-quality aquarium with moderate light for them to acquire their nutritional requirements.

They also profit from the addition of at least a 20 W incandescent light bulb in their tank to assist them to absorb certain vitamins.

The proper tank lighting will not only support their health but also bring out their natural colors and patterns.

King Angelfish Compatibility

King angelfish good tank matesKing angelfish bad tank mates
Groupers Batfish
King Angelfish Compatibility

They’ve been documented biting the fins of lionfish. They’ll also bite the eyes of sharks if they’re a coral polyp, as shown by research.

Pro Tip: It’s vital to add King Angelfish as the final resident once other fish have been established.

King Angelfish Diet

King Angelfish are omnivores that consume a wide range of foods.

Thus, they require a varied diet including:

  • Algae
  • Seaweed
  • Tunicates
  • Worms
  • Sea stars (including brittle stars)
  • Sea urchins
  • Various small mollusks
  • Sponges

King Angelfish Breeding

The king angelfish is an egg scatterer that lives in the open ocean and has gonadal activity indicating a reproductive season that runs from summer through fall, culminating in the late summer.

The actual spawning takes place on sand bottoms near a reef at sunset, when both a male and a female take part in the ritual.

Males arrive first, in a flurry of activity that includes chasing and fast swimming, resulting in transitory spawning grounds and the bigger fish congregating on the outer bounds of little groups.

After a few minutes, the females appear at the bottom alone or in small groups. When a female approaches a male, he swims towards and above her, fluttering his pelvic fins while swimming back and forth in front of her to create a fluttering movement of his body.

When it’s time for her to spawn, she’ll swim a diagonal line to the surface and then the male until they reach the surface, where they will expel eggs and sperm. The eggs and larvae are pelagic in nature.

King Angelfish Gender Difference

King angelfish are difficult to sex because there are no obvious external differences between males and females. However, some experts believe that the males may be slightly larger than the females.

The larger and more dominant fish will become male since they will be the ones to mate with all of the females in the area. The smaller, subordinate fish are usually female.

It’s conceivable that the next fish in line for power may transform into a male if a male angelfish dies or is removed from his group by an external influence such as sickness.

Possible Diseases and Prevention

White Spot Disease

The king Angelfish, like other saltwater angelfishes, is susceptible to any disease that might affect them in captivity. They are most prone to sickness if they are disturbed by bad housing or tankmates.

White spot disease Cryptocaryon irritans, also known as Marine Ich, Saltwater Ich, and Crypt is the most prevalent malady affecting marine tangs and angelfish. The primary symptoms of Marine Ick involve constant scratching that leads to lots of white spots.

Marine velvet

The velvet disease, Oodinium ocellatum (also known as Amyloodinium ocellatum or Branchiophilus Maris), is a flagellate that infects fish.

Symptoms of Marine Velvet include:

  • Peppery covering
  • Clamped fins
  • Respiratory distress (breathing rapidly as seen by frequent or rapid gill movements)
  • Eye cloudiness
  • Possible weight loss


Parasites on marine fish kept in aquariums with live rock or in a reef tank are particularly difficult to eradicate.

Copper and formalin solutions, as well as quinine-based medicines, are harmful to other marine species. However, metronidazole and other medicines are effective and safe in the treatment of a variety of protozoan and anaerobic bacterial diseases.

For external parasites, raise the temperature of your tank gradually to at least 82° F (28° C). This will prevent the parasite from completing its life cycle, which involves the attachment to fish.

Is King Angelfish Reef Safe?

King angelfish are not considered reef safe so it won’t be a good idea to keep them in a reef tank. While youngsters may live alongside stony corals, adults will harm all hard corals, clams, and soft corals.

The most noxious soft corals from the family Alcyoniidae or the Octocorals could be allowed, but they should be closely watched.

Polyps and zoanthids have been nipped at as well. Most ornamental crabs and shrimp are usually left alone, although tubeworms will be devoured.


How Big Do King Angelfish Get?

King Angelfish can grow up to 14 inches in the wild, but they are usually much smaller in captivity.

What Do King Angelfish Eat?

King Angelfish are omnivorous and will eat a variety of foods, including marine algae, small crustaceans, and zooplankton.

Do King Angelfish Need a Special Diet?

King angelfish do not need a special diet, but they will benefit from a varied diet that includes marine algae, small crustaceans, and zooplankton.

What Are the Common Health Problems of King Angelfish?

The most common health problems of king angelfish are white spot disease and marine velvet.

How Do I Prevent My King Angelfish from Getting Sick?

The best way to prevent your king angelfish from getting sick is to provide them with a clean and well-maintained aquarium.

How Do I Treat My King Angelfish If It Gets Sick?

If your king angelfish gets sick, you should seek the advice of a qualified veterinarian who is familiar with saltwater fish.

Can I Keep More Than One King Angelfish in My Aquarium?

You can keep more than one king angelfish in your aquarium, but it is best to keep them in pairs or harems.

Do King Angelfish Get Along With Other Fish?

King Angelfish are generally peaceful, but they can be aggressive towards other fish if they feel threatened. It is best to keep them with fish that are similar in size and temperament.

Do King Angelfish Need a Lot of Maintenance?

King angelfish do not need a lot of maintenance, but they do need a clean and well-maintained aquarium.

Last Words

The king angelfish is one of the most beautiful fish in the world. It’s a real standout in any aquarium. But before you add one to your tank, make sure you understand the special care they need and their potential to wreak havoc on your other tank mates.

They are relatively easy to care for as long as you provide them with a large tank, plenty of hiding places, and the right food.

We hope you enjoyed reading this article and that you found it helpful. If you have any questions or comments, please feel free to leave them below.