Can Koi Angelfish live with Carnival / Polka Dot Freshwater Crab?
Caution — with care
Why
- Carnival / Polka Dot Freshwater Crab can grab Koi Angelfish while it sleeps — only fast mid/top-water fish are reasonably safe.
- Only a narrow pH overlap — keep both around 7.5–7.5.
Sweet spot: both do well at 78–82°F and pH 7.5–7.5 — aim there.
Side-by-side
| Koi Angelfish | Carnival / Polka Dot Freshwater Crab | |
|---|---|---|
| Temperature | 78–84°F | 75–82°F |
| pH | 6–7.5 | 7.5–8 |
| Hardness (GH) | 3–12 dGH | 8–15 dGH |
| Adult size | 6" | 1.5" |
| Temperament | Peaceful | Peaceful |
| Min tank | 30 gal | 10 gal |
Together, plan on at least 30 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.
Design the whole tank, not just the stocking
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Design a tank with Koi Angelfish, Carnival / Polka Dot Freshwater Crab →Everything compatible with Koi Angelfish · …with Carnival / Polka Dot Freshwater Crab