Compatibility brief
Can Betta live with Otocinclus?
Caution. Check the issues below before buying.
Compatibility score
Profile confidence: low
Order of checkstank volume vs adults → predation mouth gap → temperament / fin nipping → shared water windows.
60L
Combined minimum footprint reference for these two species: about 60L (larger active fish often want more length).
Otocinclus are peaceful algae grazers and often look like ideal “cleanup” companions for a betta tank, but Fishori’s live verdict is CAUTION because some bettas still chase or nip small midwater and glass-working fish, especially in bare or short tanks. Otos also need a mature biofilm food supply a betta cup cannot provide. The pairing can work with a calm betta, heavy cover, and an established planted tank; it fails when people treat otos as ornaments that will survive on glass film alone beside a territorial male.
Assessment details
Temperament difference
Top issueBetta is semi-aggressive, while Otocinclus is peaceful. Expect chasing or stress unless the tank is large and heavily structured — monitor closely.
Compatible temperature range
Both fish can comfortably share similar water temperatures.
“Betta is semi-aggressive, while Otocinclus is peaceful”
Temperament difference
Next steps
Concrete changes, not "research more" filler.
- •Only try this in an established planted tank with a calm betta, a real oto group, and supplemental wafers — remove otos at the first chase.
- •Provide plenty of hiding spots and visual breaks so Otocinclus can escape if harassed.
- •Otocinclus should be kept in a group of at least 6 for best health and behaviour.
- Seriously Fish. Betta splendens
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Betta splendens
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Betta splendens
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. Otocinclus macrospilus (Otocinclus ‘affinis’ / trade oto stand-in)
Primary stand-in: SF profile for O. macrospilus. Shop 'O. affinis'/'otocinclus' labels are often misidentified. Verify the fish against a good key, not a single import sticker.
- FishBase. Otocinclus affinis
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Otocinclus affinis
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
- FishBase. Otocinclus vittatus
Taxonomy, distribution, and typical max length in natural/wild contexts (cross-check to aquarium import lines).
- Wikipedia. Otocinclus
Encyclopaedia overview; use specialist aquarium sources for your stock's real temperature/pH/footprint needs.
Try this next
Build the full stocking list with Betta + Otocinclus
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. At least one species here has common trade-name ambiguity.