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Compatibility

Compatibility brief

Can Bloodfin tetra live with Oscar?

VerdictRISKY

Risky. This mix is commonly discouraged for typical setups.

Bloodfin tetra + Oscar: Aggression mismatch. Oscar is aggressive, while Bloodfin tetra is peaceful. The aggressive fish will likely bully or harm the peaceful one. Real tanks add variables Fishori cannot model; treat this as a high-risk read, not certainty.

Compatibility score

30/100

Profile confidence: medium

Order of checkstank volume vs adults → predation mouth gap → temperament / fin nipping → shared water windows.

Min tank

300L

Combined minimum footprint reference for these two species: about 300L (larger active fish often want more length).

Temperature
Range in °C2328°C shared
Bloodfin tetraOscarShared window
pH
Range67.5 shared
Bloodfin tetraOscarShared window
Size / predation

Oscar (35cm adult) may treat small Bloodfin tetra (~5cm) as food once grown — plan adult sizes, not shop sizes.

Temperament / behaviour

Bloodfin tetra (peaceful) and Oscar (aggressive) are far apart on aggression — bullying or injury is a common outcome in average community layouts.

Assessment details

  1. Aggression mismatch

    Top issue

    Oscar is aggressive, while Bloodfin tetra is peaceful. The aggressive fish will likely bully or harm the peaceful one.

  2. Oscar may eat Bloodfin tetra

    Oscar (35cm) is predatory and Bloodfin tetra (5cm) is small enough to be eaten. This pairing is unsafe.

  3. Compatible temperature range

    Both fish can comfortably share similar water temperatures.

Oscar is aggressive, while Bloodfin tetra is peaceful

Aggression mismatch

Next steps

Concrete changes, not "research more" filler.

  • Bloodfin tetra should be kept in a group of at least 6 for best health and behaviour.

Try instead

  • Bloodfin tetra should be kept in a group of at least 6 for best health and behaviour.
  • Build a species-only tank for the larger fish, or restock with fish too large to be eaten at adult sizes.
Sources from both profiles
Only URLs that exist on the species records are shown. We do not fabricate citations.
  • Seriously Fish. Aphyocharax anisitsi

    Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).

  • FishBase. Aphyocharax anisitsi

    Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.

  • Wikipedia. Aphyocharax anisitsi

    Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.

  • 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 Bloodfin tetra + Oscar

Plan further

Try both species in the full-stock tank check, or open either fish profile for mates lists. 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. Based on multiple reputable aquarium care sources with strong agreement.