Koi Angelfish - Species Spotlight

Posted by Miles Harrison on 08/23/2022

What are Koi Angelfish?

One of the most popular aquarium breeds, the Koi angelfish (Pterophyllum scalare) is an angelfish originating from the Amazon of Peru and Ecuador. Do not be confused by the name, Koi angelfish are not related to the koi species. They get their name by the stark resemblance in both pattern and color to the koi fish but are part of the angelfish family. Similar to all angelfish, the Koi angel is a peaceful fish with a beautiful appearance and a life span of up to ten years.

Image of a Koi Angelfish
A Koi Angelfish swimming in a planted aquarium

Appearance and Disposition

The Koi angelfish stands out due to its mottled black, white, yellow, and orange coloring. They have a slender body, reaching approximately 15 centimeters in length. Although their striking looks may be the first thing to get your attention, one of the best traits of the Koi angelfish is their personality. These fish are known for their elegant, and graceful temperament. They tend to move slowly throughout the tank, which can be very peaceful to watch. Despite their gentle nature, if the angelfish senses a threat during spawning they could become territorial exhibiting more aggressive behavior. Koi angelfish generally do well with other fish, however, they do tend to eat fish smaller than they are. This is not out of aggression, but simply due to the fact that Koi angels will eat almost anything that fits in their mouth. Tank mates that do well with Koi angelfish include larger tetras and rasboras, peaceful barbs, rainbowfish, corydoras, and other medium-sized catfish.

Image of a Koi Angelfish
Koi Angelfish can be kept with other types of Angelifsh


Koi angelfish thrive in environments that mimic their native habitat with plenty of plants, driftwood, and even floating plants for shade that will provide them comfort. The plants will help keep the water clear and full of oxygen which will increase the survival rate and health of the Koi angelfish. The water temperature should be between 76 - 86 degrees Fahrenheit with a pH of approximately 6.5 -7.4. Moderate water flow is also necessary for the Koi angelfish along with medium-grade smooth gravel. The tank for a Koi angelfish should be at least 30 gallons for an individual, and higher than 30 gallons if there are more than one Koi angelfish in the tank.


The Koi angelfish species is omnivorous. In the wild, it feeds mainly on insect larvae and small fish. In captivity, they can be fed with pellets, and flakes, and will thrive being fed tubifex worms and blood worms. Koi Angelfish should be fed what they can consume in 2-3 minutes, twice per day. Keep in mind that these fish tend to be a bit slower moving, therefore if you have other quick fish in your tank it is advisable to give the Koi angelfish another feeding opportunity to ensure they are getting the correct amount of nutrition.

Image of a Koi Angelfish
Koi Angelfish should be fed twice per day.


Adult Koi angelfish will pair off and spawn. Once they form their “couple”, is when you may see some signs of aggressive, dominant behavior. Once they choose a site they find fit for spawning, they clean the surface on which to lay their eggs and chase other fish away. The female will lay rows of eggs on the prepared surface and the male will then fertilize the eggs she has laid. Many angelfish have lost the rearing instinct due to their time in captivity and may eat their own eggs or fry. Breeders typically remove the fertilized eggs from the tank with their parents and put them in a separate aquarium for the duration of their growth to avoid the chance of them being eaten.

Where can I buy a Koi Angelfish?

Occasionally, Koi Angelfish are available for sale at Local Fish Stores, Ebay and on Light Fish.