10 Fun and Interesting Angelfish Facts

Updated September 20, 2021
Angelfish (Pterophyllum scalare) in natural habitat

Angelfish are one of the most popular aquarium fish, and they certainly add a lot of grace and beauty to a tank. However, they are not always the easiest fish to care for unless you know a few facts about them and their needs.

10 Interesting Angelfish Facts

You've probably seen many lovely young angelfish at aquarium stores, but how much do you really know about them? Here are some very important facts that can help you decide if these fish are the right species for your home aquarium.

1. Freshwater Angelfish Are Members of the Cichlid Family

Angelfish are freshwater members of the cichlid family, and they originate from South America. This group includes other popular fish, such as Oscars, Jack Dempseys, parrotfish, and discus.

2. Angelfish Are Omnivores

What do angelfish eat? Angelfish will eat live foods and plants, so these omnivores need to be fed the right foods to help them reach optimum size and remain healthy.

  • It's usually best to offer a daily feeding of flakes or a pelleted diet formulated for angels.
  • Supplement the fish with live feedings of freshly hatched brine shrimp, bloodworms, and daphnia grown from your cultures to avoid contaminated sources.
  • Angelfish can also eat other fish that are in the tank that are smaller, such as fry and tetras.

3. Angelfish Can Grow to Nearly 10 Inches

How big do angelfish get and how fast do angelfish grow? On average, well-cared for angelfish will reach about 6 inches at adulthood, which is about a year and a half old. If they're housed in very large tanks and are not overcrowded, they can reach nearly 10 inches, although this would be quite rare in captivity.

Angel fish against a backdrop of vivid green aquatic plants

4. They Are Best Kept With Their Own Kind

Are angelfish aggressive? These fish are often thought of as community fish, meaning they can live with a variety of other tropical species.

  • While this is true when they're young, angels become more territorial and aggressive as they mature. For this reason, it's usually better to house them in a separate tank as adults.
  • Angelfish can also become aggressive with each other, which usually occurs during breeding times. Males can fight with other males over mates, and females can be aggressive when protecting their offspring from other male and female fish looking for a snack.
  • Just as angelfish may prey on smaller fish, an angelfish "predator" can be any fish that's larger and carnivorous, or equally territorial, such as a betta, which should never be housed with angelfish.

5. Angelfish Aquariums Require Specific Conditions

Always keep angelfish in the cleanest, largest size tank you can support, and make sure you have a good filtration system that doesn't create excessive currents in the water, because angels aren't the most agile swimmers. The right water conditions can also lessen stress on your angels and keep them healthier and happier. With proper water conditions, you can expect the angelfish lifespan to be up to 10 years.

Pterophyllum scalare, angelfish or freshwater angelfish

Ideally, these fish prefer:

  • Angelfish water temperature range of 74 to 78 degrees Fahrenheit when kept as pets
  • Temperature of 80 degrees for spawning
  • Average pH range of 6.5 to 6.9

6. Angelfish Are Prone to Ich

Ich (sometimes called ick) is an opportunistic parasitic condition that can strike at any time the conditions in the tank are right, and angelfish are highly susceptible to it. The parasite can spread from one fish to another, and it can also exist in the tank on its own before attaching to a fish. Overcrowding, poor water conditions, and improper diet can all contribute to ich infestation.

7. Angelfish Lay Eggs

Fish either give birth to live babies or they lay eggs that are fertilized and hatched later. Angels fall in the egg-laying category. The process for angelfish egg laying and hatching are:

  1. The female prefers to deposit her eggs in neat rows on a piece of submerged slate leaned against a wall of the tank.
  2. The male will follow up behind her and use his own papilla to fertilize each egg individually.
  3. If the fertilization was successful, you'll notice the fry begin wiggling their tails in about two days, even though they're still attached to the slate.
  4. The fry will become free-swimming sometime around day five, and they will begin eating on their own around day seven once they have absorbed the yolk sacks from their eggs.
Aquarium Fish- Black Scalare in water

8. Female and Male Angelfish Look the Same

Unlike some breeds of fish, you usually can't tell a male angel from a female just by looking at them unless the female is ready to breed.

  • Both sexes have an organ called a papilla located between their anal and ventral fins.
  • When the female becomes gravid, which means she is carrying eggs, her papilla becomes slightly enlarged and has a blunt tip. When the male senses a gravid female, his papilla also enlarges slightly, but it has a more pointed tip. This is the main way to distinguish between the sexes, but it's not foolproof.
  • You can always be certain that any angel that lays eggs is a female. Any other angels in the tank that don't become gravid or don't respond to a gravid female may either be more females or males that aren't interested in pairing up and breeding.

9. There Are Many Types and Colors of Freshwater Angelfish

The original freshwater angelfish was a standard silver angelfish. However, mutations in the standard coloring have occurred, and breeders have capitalized on them to create many interesting and beautiful varieties. One of the most recent is the Philippine Blue angelfish, which actually displays some blue coloration as seen in the following video of a breeding pair and their 7-day-old offspring.

Other popular varieties and colors include, but are not limited to:

  • Marbles
  • Zebras
  • Leopards
  • Half blacks
  • Whites
  • Veils
  • Golds
  • Black and whites

10. There Are Also Marine Angelfish

There are also many species of marine angelfish in an array of colors that rival the rainbow, and each has their own care requirements. If you think you're up to the challenges of maintaining a saltwater tank, you'll find fascinating specimens at any aquarium shop that specializes in saltwater fish.

Angelfish Are Rewarding Species for Hobbyists

Even though angelfish do present a few challenges for their keepers, they still aren't as difficult to manage as some of their other cichlid relatives, such as discus. Give them as large a tank as you possibly can, keep their water very clean, and feed them a carnivorous diet. If you can do that, you just might be able to raise your juvenile angels up to become amazingly impressive adults.

10 Fun and Interesting Angelfish Facts