Fish of the month · October 2026
Neon tetra
Paracheirodon innesi
Peaceful, shy and schooling: a beginner fish with one caveat. Add them to an established tank, never a new one.
Neon tetra hero photo — school in planted tank
- Size
- Up to 3 cm
- Tank
- 54 L min
- Temp
- 22–26 °C
- pH
- 6.0–7.0
- School
- 8+
- Difficulty
- Beginner
Why it needs a school
Neons school loosely when relaxed and tightly when stressed. Keep at least 8, in a tank of at least 54 litres (a 60 × 30 cm footprint) for a school of 8–10. Longer footprints beat tall ones; they swim mid-water in a horizontal band.
How to keep one
Add them to an established tank, never a new one: they are very sensitive to ammonia and nitrite, which should stay at 0 ppm. Keep them with similarly sized peaceful fish, and avoid angelfish, which may eat them. Almost all stock is commercially bred.