Oscar tank mates
Massive personality, even more massive tank requirement. A single oscar realistically needs 300L+ and produces enough waste to push your filter to its limit.
Lists below are built from this species record (safest, best with, risky, unsafe) — each link opens a pair-level check, not a guarantee.
Best tank mates (on file)
Merged from conservative safest and best with fields — de-duplicated by species.
The Oscar profile lists Common Pleco as both safe and a recommended pairing. Common Pleco is a peaceful intermediate-care species with a 600L minimum. Run the pair checker for your specific tank before stocking.
The Oscar profile lists Green Terror as both safe and a recommended pairing. Green Terror is a aggressive intermediate-care species with a 300L minimum. Run the pair checker for your specific tank before stocking.
The Oscar profile lists Jack Dempsey as both safe and a recommended pairing. Jack Dempsey is a aggressive intermediate-care species with a 200L minimum. Run the pair checker for your specific tank before stocking.
Risky or situational
From risky tank mates and broad avoid with (excluding “unsafe” below). May work with species-only setups, more water, or mature systems — read the pair page.
None on file beyond the safe list.
Fish to avoid with Oscar
From the unsafe list — predation, aggression, or space rules on this profile.
Oscar is flagged as predatory or as likely to eat small fish, and Neon Tetra at 4cm is well within an adult Oscar's gape.
Oscar is flagged as predatory or as likely to eat small fish, and Guppy at 5cm is well within an adult Oscar's gape.
Oscar is flagged as predatory or as likely to eat small fish, and Corydoras Catfish at 6cm is well within an adult Oscar's gape.
Angelfish conflicts with Oscar on temperament, predation, or footprint. The juvenile size in a shop tank is not the figure that matters here.
Discus conflicts with Oscar on temperament, predation, or footprint. The juvenile size in a shop tank is not the figure that matters here.
Oscar is flagged as predatory or as likely to eat small fish, and Tiger Barb at 7cm is well within an adult Oscar's gape.
Tank size and groups
- Published minimum for Oscar: 300L — group minimum 1 .
- Compatibility changes when the tank is too short for turning, too little for a real school, or too warm for one species and not the other — that is why pair checks include tank context, not only temperament.
- Nearest litre hub to this minimum: 300L hub.
Easier alternatives to consider
Conservative beginner-peaceful picks from the library — not replacements for reading, but a shorter on-ramp than this species for a first tank.
Plan before you buy
Pair checks for every mix, then multi-species stocking in the builder.
Filtration & heating
A 300L minimum tank for Oscar needs a filter rated for at least 1200L/hr turnover and a heater maintaining 23–28°C.
Similar fish (same category)
- Green Terror — min 300L
- Severum — min 250L
- African Cichlid — min 200L
- Convict cichlid — min 200L
- Discus — min 200L
- Firemouth Cichlid — min 200L
- Jack Dempsey — min 200L
- Keyhole cichlid — min 200L
Related (care + temperament)
Other species that list Oscar
Reverse lookup: these profiles reference Oscar under safe or “best with” lists.