Oscar Tropical Fish Information

Astronotus ocellatus
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

Oscar (Astronotus ocellatus)

Oscar Tropical Fish Learn all about the Oscar's feeding habits and food types, its behaviour, its origins, its natural habitats, is it male or female, breeding advice and information, suitable tank mates, its sizing and growth range, minimum tank size, water PH and more. Use our fish community creator tool to plan your tank set up and ensure that the Oscar is the right fish for your aquarium.

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.

Oscar Facts

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

Oscar Help and Advice

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 caring for and keeping fish like these.

Check tank mates for the Oscar fish species

You are in the thinkfish community creator for the Oscar fish species, you can learn all about how the tool works in assessing fish tank mate compatibility at the link provided or use the tool tips provided to guide you. Create a test fish community that includes the Oscar species and any other types of fish or crustacean you'd like to introduce - You can assess the best companions, tank size suitability, stocking levels based on filter type and volume and possible negative interactions and warnings as you build up your aquarium.

Please do check your water type for compatibility with your fish, which can be found on the Oscar information box above and your local water company providers website. Don't waste your money and endanger your fish!
Tank Details
question mark  Rename your tank:
question mark  Length: (cm)
question mark  Volume: (Litres)
question mark  Filter type:

* Recent changes to stocking & filter advice October 2018
* This fishtank will only last for this session - to save your tank please Join/Log in

question mark  Max Stocking level: 0cm
0-1 months 20%: 0cm
1-3 months 40%: 0cm
3-6 months 60%: 0cm
question mark  Current stock level: 0cm
Stock percentage: 0%
question mark  Suggested maximum
fish size for your tank:
My Fishtank Quantity Stock cm

There are currently no fish in your fish tank. To add fish, you can click the 'Add the Oscar to your tank' button. Or search for a different fish using the options presented above

sample fish tank
See an example tank as it would show on a user profile with enabled settings and community tanks.

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