Can Swordtail live with Red-Line Rasbora?
Caution — with care
Why
- No overlapping water hardness: Swordtail wants 12–30 dGH but Red-Line Rasbora wants 1–8 dGH.
- Only a narrow pH overlap — keep both around 7–7.
- Swordtail is semi-aggressive — give the peaceful Red-Line Rasbora plenty of space, cover and broken sight lines.
- Large size gap (Swordtail 5.5" vs Red-Line Rasbora 1.75") — watch that the smaller one gets its share at feeding time.
Sweet spot: both do well at 73–81°F and pH 7–7 — aim there.
Side-by-side
| Swordtail | Red-Line Rasbora | |
|---|---|---|
| Temperature | 72–82°F | 73–81°F |
| pH | 7–8.4 | 5–7 |
| Hardness (GH) | 12–30 dGH | 1–8 dGH |
| Adult size | 5.5" | 1.75" |
| Temperament | Semi-aggressive | Peaceful |
| Min tank | 29 gal | 15 gal |
Together, plan on at least 29 gallons.
How to make it work
- Target the overlapping water-parameter range and acclimate slowly.
- 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 Swordtail, Red-Line Rasbora →Everything compatible with Swordtail · …with Red-Line Rasbora