Compatibility brief
Can Celebes Rainbowfish live with Oscar?
Risky. This mix is commonly discouraged for typical setups.
Compatibility score
Profile confidence: low
How we decideFishori checks adult size and predation risk, behaviour, water requirements and tank needs before giving a verdict.
300L
Combined minimum footprint reference for these two species: about 300L (larger active fish often want more length).
Oscar (about 35cm as an adult) can realistically eat Celebes Rainbowfish (about 7cm) once grown. Plan around adult sizes, not shop sizes.
Celebes Rainbowfish (peaceful) and Oscar (aggressive) are far apart on aggression — bullying or injury is a common outcome in average community layouts.
Assessment details
Aggression mismatch
Top issueOscar is aggressive, while Celebes Rainbowfish is peaceful. The aggressive fish will likely bully or harm the peaceful one.
Oscar may eat Celebes Rainbowfish
Oscar (35cm) is predatory and Celebes Rainbowfish (7cm) is small enough to be eaten. This pairing is unsafe.
Compatible temperature range
Both fish can comfortably share similar water temperatures.
“Oscar is aggressive, while Celebes Rainbowfish is peaceful”
Aggression mismatch
Next steps
Concrete changes, not "research more" filler.
- •Celebes Rainbowfish should be kept in a group of at least 6 for best health and behaviour.
- •Oscar reaches ~35cm: tank length and turning room matter more than the litre number. A tall, short tank of the same volume is not equivalent.
Try instead
- →Build a species-only tank for the larger fish, or restock with fish too large to be eaten at adult sizes.
- Seriously Fish. Marosatherina ladigesi
Primary: species page on Sulawesi limestone-stream origin (which explains the hard alkaline water requirement) and the extended-fin display in males.
- Practical Fishkeeping. Celebes Rainbowfish Profile
Secondary: editor coverage of stocking, water chemistry, and the colour development that needs months of stable water.
- Seriously Fish. Astronotus ocellatus
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Astronotus ocellatus
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Astronotus ocellatus
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
- Wikipedia. Astronotus ocellatus (oscar)
Encyclopaedia overview; use specialist aquarium sources for your stock's real temperature/pH/footprint needs.
Try this next
Build the full stocking list with Celebes Rainbowfish + Oscar
Plan further
Check each species’ mates list, size the glass, then verify the full stock in the builder. Methodology explains how verdicts are produced.
Individual fish vary in personality. Fishori uses conservative hobby rules. Observe any new introduction closely, feed thoughtfully, and keep a quarantine or backup plan. This is not veterinary advice.
Profile data confidence: medium. Driven by the lower-confidence profile (Celebes Rainbowfish): Typical care sources — real tanks still vary.

