Compatibility brief
Can Oscar live with Red-tailed catfish?
Risky. This mix is commonly discouraged for typical setups.
Oscar + Red-tailed catfish: Red-tailed catfish may eat Oscar. Red-tailed catfish (120cm) is predatory and Oscar (35cm) is small enough to be eaten. This pairing is unsafe. Real tanks add variables Fishori cannot model; treat this as a high-risk read, not certainty.
Compatibility score
Profile confidence: medium
Order of checkstank volume vs adults → predation mouth gap → temperament / fin nipping → shared water windows.
2000L
Combined minimum footprint reference for these two species: about 2000L (larger active fish often want more length).
Red-tailed catfish (120cm adult) may treat small Oscar (~35cm) as food once grown — plan adult sizes, not shop sizes.
Assessment details
Compatible temperaments
Both Oscar and Red-tailed catfish share a aggressive temperament.
Red-tailed catfish may eat Oscar
Top issueRed-tailed catfish (120cm) is predatory and Oscar (35cm) is small enough to be eaten. This pairing is unsafe.
Compatible temperature range
Both fish can comfortably share similar water temperatures.
“Red-tailed catfish (120cm) is predatory and Oscar (35cm) is…”
Red-tailed catfish may eat Oscar
Next steps
Concrete changes, not "research more" filler.
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. 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.
- Seriously Fish. Phractocephalus hemioliopterus
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Phractocephalus hemioliopterus
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Phractocephalus hemioliopterus
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
Try this next
Build the full stocking list with Oscar + Red-tailed catfish
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.