Can Black Molly live with Royal Pleco?
Caution — with care
Why
- Very different sizes (Royal Pleco 17" vs Black Molly 4") — these two need different tanks, and the smaller fish will be out-competed at feeding time.
- Only a narrow water hardness overlap — keep both around 12–12 dGH.
Sweet spot: both do well at 73–82°F and pH 7–7.5 — aim there.
Side-by-side
| Black Molly | Royal Pleco | |
|---|---|---|
| Temperature | 72–82°F | 73–82°F |
| pH | 7–8.5 | 6.5–7.5 |
| Hardness (GH) | 12–30 dGH | 4–12 dGH |
| Adult size | 4" | 17" |
| Temperament | Peaceful | Peaceful |
| Min tank | 30 gal | 120 gal |
Together, plan on at least 120 gallons.
How to make it work
- Target the overlapping water-parameter range and acclimate slowly.
Sort it with: A larger tank · GH remineraliser
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Design a tank with Black Molly, Royal Pleco →Everything compatible with Black Molly · …with Royal Pleco