How Many Rainbow Shark in a 125-Gallon Tank?
In a 125-gallon tank, plan on about 1–2 Rainbow Shark, leaving room for tankmates and filtration headroom.
Why
Stocking is driven by adult size and waste output, not just fish count. Rainbow Shark reaches about 6" with a heavy bioload, and needs 72–81°F water at pH 6.5–7.5. Always cycle the tank and test water before adding livestock.
| Adult size | 6" |
|---|---|
| Minimum tank | 55 gallons |
| Temperature | 72–81°F |
| pH | 6.5–7.5 |
| Temperament | Semi-aggressive |
| Schooling | No |
| Diet | Omnivore |
| Care level | Easy |
| Origin | Southeast Asia |