Can Black Molly live with Swordtail?
Light caution
Why
- Swordtail is semi-aggressive — give the peaceful Black Molly plenty of space, cover and broken sight lines.
Sweet spot: both do well at 72–82°F and pH 7–8.4 — aim there.
Side-by-side
| Black Molly | Swordtail | |
|---|---|---|
| Temperature | 72–82°F | 72–82°F |
| pH | 7–8.5 | 7–8.4 |
| Hardness (GH) | 12–30 dGH | 12–30 dGH |
| Adult size | 4" | 5.5" |
| Temperament | Peaceful | Semi-aggressive |
| Min tank | 30 gal | 29 gal |
Together, plan on at least 30 gallons.
How to make it work
- Use a larger, well-decorated tank with sightline breaks, keep everyone well-fed, and add the calmer fish first.
Sort it with: GH remineraliser
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Design a tank with Black Molly, Swordtail →Everything compatible with Black Molly · …with Swordtail