Behaviour Aggressive, destructive, pair forming
Typical size 40cm
Max size 50cm
Tank Area All
Min Tank Size 150cm
Temp Min: 24℃ Max: 28℃
Feeding Pellet, frozen, live, meaty foods
pH Range 6-8.5
Hardness vs,s,m,h,vh
Oscar Astronotus ocellatus
  • Oscar Astronotus ocellatus - thumbnail
  • Red White Oscar Astronotus ocellatus - thumbnail
  • Albino Oscar Astronotus ocellatus - thumbnail
  • Red Oscar Astronotus ocellatus - thumbnail


Astronotus ocellatus

The Oscar is well known to many fishkeepers, as it will become very involved with its owners, working out how to 'ask' for food and on occasion acting differently towards different humans. Although Oscars make excellent 'pet' fish, they should be chosen with serious thought. Their mild aggression is constant and at 40cm they demand a large aquarium, in which they will regularly move decor around as it suits them. Although aggressive, in a large aquarium they can be kept in small groups and/or with other large, hardy fish where despite the occasional squabble, they will accept and get along with their tank mates. Meaty foods are an important part of the diet but it should be noted that many Oscars die early due to overfeeding. Despite the Oscars constant begging for food, they eat far more than they need to, and once they reach over 20cm, they should only be fed once every other day. An albino variety is also available.

Due to their aggression and size, and that no fish can be mixed with certainty of success, Oscars are excluded from the Compatibility Checker

This fish is excluded from the Compatibility Checker as it is unsuitable for community aquariums or may require expert care.

Family Cichlidae (Cichlids) | Synonyms Labotes ocellatus, Acara ocellatus | Other names Marble Cichlid, Red Oscar, Velvet Cichlid | Origin South America; Amazon River basin | Natural Water Conditions pH 6-8, soft to hard | Natural Habitat Relatively quiet sandy-bottomed shallow waters

Have a Oscar Problem or General Question?

If you have a question about keeping Oscar's then please use our Oscar help forum. Join 100's of other fish enthusiasts with 1000's of years experience between them.

Think Fish Community Creator - Oscar

Please check your water type for compatibility with your fish, which can be found on the Oscar information box.

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