How Many Bloodfin Tetra in a 20-Gallon Tank?
In a 20-gallon tank you can comfortably keep about 6–16 Bloodfin Tetra. As a schooling species, never keep fewer than 6.
Why
Stocking is driven by adult size and waste output, not just fish count. Bloodfin Tetra reaches about 2" with a moderate bioload, and needs 64–82°F water at pH 6–8. Always cycle the tank and test water before adding livestock.
| Adult size | 2" |
|---|---|
| Minimum tank | 20 gallons |
| Temperature | 64–82°F |
| pH | 6–8 |
| Temperament | Semi-aggressive |
| Schooling | Yes — group of 6+ |
| Diet | Omnivore |
| Care level | Easy |
| Origin | Paraná basin |