How Many Common Pleco in a 125-Gallon Tank?
In a 125-gallon tank, plan on about 1–1 Common Pleco, leaving room for tankmates and filtration headroom.
Why
Stocking is driven by adult size and waste output, not just fish count. Common Pleco reaches about 18" with a heavy bioload, and needs 72–82°F water at pH 6.5–7.8. Always cycle the tank and test water before adding livestock.
| Adult size | 18" |
|---|---|
| Minimum tank | 125 gallons |
| Temperature | 72–82°F |
| pH | 6.5–7.8 |
| Temperament | Semi-aggressive |
| Schooling | No |
| Diet | Herbivore |
| Care level | Moderate |
| Origin | South America |