Can Discus live with Swordtail?
Caution — with care
Why
- Almost no shared temperature: Discus wants 82–88°F and Swordtail wants 72–82°F, so only 82°F suits both — too fine a margin to actually hold.
- No overlapping water hardness: Discus wants 1–8 dGH but Swordtail wants 12–30 dGH.
- Only a narrow pH overlap — keep both around 7–7.
- Swordtail is semi-aggressive — give the peaceful Discus plenty of space, cover and broken sight lines.
Sweet spot: both do well at 82–82°F and pH 7–7 — aim there.
Side-by-side
| Discus | Swordtail | |
|---|---|---|
| Temperature | 82–88°F | 72–82°F |
| pH | 5.5–7 | 7–8.4 |
| Hardness (GH) | 1–8 dGH | 12–30 dGH |
| Adult size | 8" | 5.5" |
| Temperament | Peaceful | Semi-aggressive |
| Min tank | 55 gal | 29 gal |
Together, plan on at least 55 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: An adjustable heater · GH remineraliser
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Design a tank with Discus, Swordtail →Everything compatible with Discus · …with Swordtail