Oscar Fish – Care, Size, Food, Tank Mates & Details!

Oscar Fish (Astronotus ocellatus) Before being named as Oscar, it was given the name of seafaring genus classification Lobotes. There are many other names for this fish species, including ‘Peacock cichlid’.

This name was often confused for the name of a peacock of Aulonocara species from Africa’s Lake Malawi.

Most of the Oscar Fish related species in South America are also known as peacock cichlids. Because of their color variation, Oscars are also known as marble cichlids and velvet cichlids.

Quick Stats

Scientific Name: Astronotus ocellatus
Care Level: Moderate
Temperament: Aggressive/Territorial
Color Form: Various
Lifespan: Up to 20 Years
Size: Up to 12 inches
Diet: Omnivorous
Family: Cichlidae
Minimum Tank Size: 55 gallons
Tank Set-Up: Freshwater: Rocks and Caves
Compatibility: Large, Passive Fish

Oscar Fish Habitat

Often viewed as a human nourishment source in most of its wild habitat, the Oscar fish is an intelligent and beautiful fish species.

It can be found in parts of French Guiana, Colombia, Ecuador Brazil, and Peru. The present population purportedly exists in Australia, Florida, and China.

These velvet cichlids can be up to 14 inches long in the wild, whereas the Oscar Fishes that are kept in aquariums only grow up to 11 to 12 inches, weigh around 3.5 pounds, and can live for eleven to thirteen years.

Oscar Fish Appearance

Wild velvet cichlids usually have a pattern of yellow spots (which gives them the name of Astronotus ocellatus) and are usually found in dark colors like brown. The color of young cichlids is different from the adult ones.

Young Oscars have spotted heads and orange stripes on their body. The species can change its color and contrasts both to mix into its territory and also for ritualized territorial combat.

For the Oscars that are kept in aquariums, their color hue can range from black to an extremely pale cream shading with differing measures of dotting and even high-contrast mottling.

Red-colored Oscars are sold as Tiger Oscars. Intensely finned varieties have likewise been created. Some of the types of Oscar fish are albino tiger Oscar tiger, albino Oscar, red Oscar fish, and veil tail Oscar fish.

Sexual development is at roughly 1 year and they can breed for over 10 years. Guardians will both clear a level space in the substrate to harbor eggs and both will take an interest in brood tending.

Oscar is very territorial just like most of the cichlids. An Oscar pair will tolerate one another, yet ordinarily, the best option is that the pair is acquainted with another tank at the same time when introduced.

Most Oscars can cohabitate with adequate space, but adding a new oscar to the already existing population rarely works.

 Oscar Fish Feeding

The wild Oscars eat different kinds of crustaceans and insects. Live food is healthy for Oscars but a diet of live food in large quantities can also be harmful to the fish as it can cause fatty liver disease, parasites, and obesity.

For the oscar fish that are kept in aquariums, they eat many types of food and are likely to taste anything you add to the aquarium.

However, the best food for them is a balance of processed food and live food. When you are buying food for your Oscar Fish, make sure the food bits are smaller than the size of the Oscars’ mouth.

You can also feed them mealworms, prawns, and shrimps from time to time. Furthermore, they also eat smaller size fish.

It is advised that the feeder fish you plan to feed to the Oscars should be raised by you since the feeder fish you purchase from farms and local markets can transmit diseases to the oscar fish.

Red minnows and guppy fish are a good choice as feeder fish, as they are affordable and disease-free.


It is very easy to find processed food for Oscars in pet stores. Brine shrimp, jumbo krill, beef heart, and bloodworms are suitable processed food for Oscar fish.

Wafers, flakes, tablets, and general cichlid pellets can also be fed to Oscars.

Other than processed food, fruits, or nuts that are found in South America also be fed to Oscar Fish. However, it should be kept in mind that the wild Oscars only eat this food on a seasonal basis.

According to aquarists’, peas are the best vegetable for Oscar Fishes as these can enhance the color of the fish. However, since this species of fish is a predatory animal, the base of their diet should always be meaty food.

But you must offer a variety of food and supplement to the Oscars to keep them well-fed and healthy.

Oscar’s are Smart? Really?

Oscar cichlids are known to be highly intelligent fish. Unlike most tropical fish, this species seems to be aware of what’s going on outside their aquarium.

It is no surprise to see the Oscars getting excited to see their owners, wagging their tail and swimming back and forth to get the attention as soon as their owner enters the room where the aquarium is placed.

Often Oscars are also called water and river dogs because their excitement resembles that of a little puppy.

Oscar Fish Aggression

You can label Oscars as somewhat semi-aggressive as compared to many other fish species, the Oscars are quite average at tolerating other fish.

However, some oscar cichlid species are highly aggressive as they show no tolerance towards other fish living in their tanks, even if they are of their species. Hence, oscar cichlids are aggressive to their tankmates.

However, this aggression can be avoided if you give these fish a tank of the correct size, preferably 55 gallons for one adult male oscar cichlid.

If you decide to add more cichlids and other species of fish, you must consider shifting all your fish to a larger tank. As soon as the Oscars reach a length of 10-12 inches and start reproducing, they can become more aggressive.

Oscar Fish Tank Mates

The tankmates of Oscars can be large armored sailfin pieces, Jack Dempsey fish, green terror, common pleco fish, and Jaguar cichlid.

These fish are good at protecting themselves but any other species of fish put into the tank will certainly be bitten or harmed by oscar cichlids.

When the Oscars are being aggressive to their fellow tank mates, they tend to flare their gills and open their mouths as wide as they can to make their heads appear bigger.

Oscars are also likely to get aggressive during tank maintenance. While most of the oscar cichlids do not harm their owners, it is still possible that they might inflict some minor wounds if you are not careful.

Oscar Fish Breeding

When Oscars become reproductive, they mostly lay spawns in the tank itself. You don’t have to create a spawning pond on purpose for Oscars if they are the only fish in the aquariums.

One thing that should be kept in mind is that even though Oscars are small in size, they still are very hyperactive and aggressive especially when there is any movement or loud noises near their tanks.

This holds, particularly during their spawning period. In worst-case scenarios, the Oscars might eat the eggs or juveniles themselves.

Tiger Oscar in a fury may effortlessly hurt or kill fish of much larger sizes if they think that they pose a risk to their eggs or young ones. If there are some other Oscars in the tank and the security of the juveniles is threatened, it’s smarter to have a different tank of around 30 gallons limit.

This might encourage more spawning as well. The best outcome comes from tanks that have dimensions of approximately 100 cm x50 cm x50cm.

While it is better to place a big flat rock at the bottom of the aquarium where the spawns are present, the substrate is not important. The water should be kept neutral and the temperature of the water should be raised from 26 to 28 degrees Celsius.

When Oscars are laying spawns, their color becomes very bright, their body color may deepen to dark black and the spots on their body become bright red. In the beginning, male Oscars might not be good at tolerating the female Oscars.

However, once the pair is separated with a glass barrier for a few days the male becomes much more tolerable towards the female Oscar.

Oscar Fish Life Expectancy

The lifespan of oscar fish depends upon the quality of the care it is receiving. The average lifespan of this species is around ten to twelve years. A proper diet though can extend the life expectancy of an Oscar up to another three to four years if taken well care of.

Another factor that has an impact on Oscar’s life expectancy is the size of their tank.

If they are put in a limited space, they won’t grow to their actual size. This decreases not only their lifespan but can also harm their internal organs as well.

Therefore, it is recommended that before you decide to get Oscars, you must go through an Oscar fish care sheet to get detailed information on their nature, breeding, diet, and care.

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