Can Harlequin Rasbora live with Molly?
Caution — with care
Why
- Only a narrow water hardness overlap — keep both around 12 dGH.
- Molly is large enough to threaten a small Harlequin Rasbora — usually fine once both are adult, but watch new additions.
Sweet spot: both do well at 72–80°F and pH 7–7.5 — aim there.
Side-by-side
| Harlequin Rasbora | Molly | |
|---|---|---|
| Temperature | 72–80°F | 72–82°F |
| pH | 6–7.5 | 7–8.5 |
| Hardness (GH) | 2–12 dGH | 12–30 dGH |
| Adult size | 1.75" | 4" |
| Temperament | Peaceful | Peaceful |
| Min tank | 15 gal | 30 gal |
Together, plan on at least 30 gallons.
How to make it work
- Target the overlapping water-parameter range and acclimate slowly.
Sort it with: GH remineraliser → Aquarium Co-Op
Where to buy
- Harlequin Rasbora: buy at Flip Aquatics · Flip Aquatics live-arrival guarantee
- Molly: buy at Flip Aquatics · Flip Aquatics live-arrival guarantee
Live-animal shipping: add a heat pack below 50°F, expect weather holds above 90°F, and schedule delivery for a moderate week when someone can receive it promptly.
Build a full tank around this stocking →Everything compatible with Harlequin Rasbora · …with Molly