Compatibility brief
Can Neon Tetra live with Oscar?
Risky. This mix is commonly discouraged for typical setups.
Compatibility score
Profile confidence: medium
Order of checkstank volume vs adults → predation mouth gap → temperament / fin nipping → shared water windows.
300L
Combined minimum footprint reference for these two species: about 300L (larger active fish often want more length).
Oscar (35cm adult) may treat small Neon Tetra (~4cm) as food once grown — plan adult sizes, not shop sizes.
Neon Tetra (peaceful) and Oscar (aggressive) are far apart on aggression — bullying or injury is a common outcome in average community layouts.
Assessment details
Known incompatible pairing
Top issueOscars will eat neon tetras. These fish are completely incompatible for any normal aquarium.
Aggression mismatch
Oscar is aggressive, while Neon Tetra is peaceful. The aggressive fish will likely bully or harm the peaceful one.
Oscar may eat Neon Tetra
Oscar (35cm) is predatory and Neon Tetra (4cm) is small enough to be eaten. This pairing is unsafe.
Compatible temperature range
Both fish can comfortably share similar water temperatures.
“Oscars will eat neon tetras”
Known incompatible pairing
Next steps
Concrete changes, not "research more" filler.
- •Neon Tetra 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. Paracheirodon innesi
Supports: aquarium size, water chemistry, temperament and compatibility (primary care reference).
- FishBase. Paracheirodon innesi
Supports: taxonomy and wild maximum size — translate to tank stocking, not a target number.
- Wikipedia. Paracheirodon innesi
Supports: general species background and common-name orientation only.
- 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 Neon Tetra + 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: high. Checked against several solid care sources that mostly agree.

