Oscar
Astronotus ocellatus
Photo: Wikipedia / Wikimedia Commons
A pet, not a community fish. 75 gallons for one, more for a pair, and a filter you will actually clean. They know who you are.
A large cichlid that acts like a dog.
In the tank
- Interactive. That is the whole point.
- Water
- freshwater
- Temperament
- Aggressive
- Swims
- All levels
- Adult size
- 12 in
- Minimum tank
- 75 gal
- Group
- Can be kept singly
- Temperature
- 74–81°F
- pH
- 6.0–8.0
- Diet
- Large cichlid pellets. Skip feeder goldfish; they are a disease vector.
- Beginner
- Not a first fish
How to keep them
- 75 gallons for one. Filter you will actually clean.
- Skip feeder goldfish — disease vector.
Tankmates
Other similarly tough large fish in a huge tank, or a species tank.
Avoid
Anything that fits in an oscar mouth. Most things do.
Check tankmates · Stocking calculator
Same group
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Pterophyllum scalare
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A real centrepiece in a 29 with height.
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Mikrogeophagus ramirezi
A small South American cichlid for a warm sand bed.
Personality in a 20+ planted tank without oscar drama.
Electric Yellow Cichlid
Labidochromis caeruleus
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Grazes aufwuchs on rock in a Malawi setup.
Jack Dempsey
Rocio octofasciata
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One adult is the show. They know the glass is a wall.
Convict Cichlid
Amatitlania nigrofasciata
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Hardy cichlid for a species tank.
Discus
Symphysodon spp.
Show fish with show requirements.
A planted discus tank is the look people steal for photos.