Compatibility brief
Can Betta live with Sailfin Molly?
Caution. Check the issues below before buying.
Compatibility score
Profile confidence: medium
Order of checkstank volume vs adults → predation mouth gap → temperament / fin nipping → shared water windows.
120L
Combined minimum footprint reference for these two species: about 120L (larger active fish often want more length).
Temperament gap (semi-aggressive vs peaceful) — needs space, structure, and careful observation, not a “drop and forget” mix.
Assessment details
Temperament difference
Top issueBetta is semi-aggressive, while Sailfin Molly 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.
Narrow pH overlap
These fish can share water but their ideal pH ranges overlap only slightly. Aim to keep pH stable in the shared range.
Hardness preference mismatch
Betta prefers soft water and Sailfin Molly prefers hard water. One of them lives outside its comfort band long-term — pick the tank's water for the more sensitive species.
“Betta is semi-aggressive, while Sailfin Molly is peaceful”
Temperament difference
Next steps
Concrete changes, not "research more" filler.
- •Provide plenty of hiding spots and visual breaks so Sailfin Molly can escape if harassed.
- 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. Poecilia latipinna
Supports: aquarium size, water chemistry, temperament and compatibility (primary care reference).
- FishBase. Poecilia latipinna
Supports: taxonomy and wild maximum size — translate to tank stocking, not a target number.
- Wikipedia. Poecilia latipinna
Supports: general species background and common-name orientation only.
Try this next
Build the full stocking list with Betta + Sailfin Molly
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.