Can Discus live with Fiddler Crab?
Caution — with care
Why
- Fiddler Crab can grab Discus while it sleeps — only fast mid/top-water fish are reasonably safe.
- Almost no shared temperature: Discus wants 82–88°F and Fiddler Crab wants 72–82°F, so only 82°F suits both — too fine a margin to actually hold.
- No overlapping pH: Discus wants 5.5–7 but Fiddler Crab wants 7.5–8.5.
- No overlapping water hardness: Discus wants 1–8 dGH but Fiddler Crab wants 15–25 dGH.
Side-by-side
| Discus | Fiddler Crab | |
|---|---|---|
| Temperature | 82–88°F | 72–82°F |
| pH | 5.5–7 | 7.5–8.5 |
| Hardness (GH) | 1–8 dGH | 15–25 dGH |
| Adult size | 8" | 2" |
| Temperament | Peaceful | Peaceful |
| Min tank | 55 gal | 15 gal |
Together, plan on at least 55 gallons.
How to make it work
- Only combine with fast, mid/top-water fish and give the tankmates plenty of escape routes.
- Target the overlapping water-parameter range and acclimate slowly.
Sort it with: An adjustable heater · GH remineraliser
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Design a tank with Discus, Fiddler Crab →Everything compatible with Discus · …with Fiddler Crab