What Size Tank Does a Rummynose Tetra Need?
Minimum tank: 20 gallons
A Rummynose Tetra (Hemigrammus rhodostomus) grows to about 2 in (5.1 cm), so the practical minimum is a 20-gallon aquarium. Because the Rummynose Tetra is a schooling fish, keep at least 6 together — a shoal needs more swimming room than one fish, so size up for a full group plus tankmates.
| Single fish or pair | 20 gallons |
|---|---|
| Comfortable group | 30 gallons |
| Community setup | 30 gallons+ |
Bigger is easier: more water dilutes waste and holds temperature and pH steady. See stocking ideas for a 20-gallon tank or try the stocking calculator.
Frequently asked questions
What is the minimum tank size for a Rummynose Tetra?
At least 20 gallons. Keep a group of 6+, which prefers something larger.
Can a Rummynose Tetra live in a smaller tank?
Going under 20 gallons stresses the fish, worsens water quality and shortens its life — not recommended.
More on this species: Rummynose Tetra full care guide · tank size · temperature · pH & hardness · tank mates