What size tank do head-and-tail-light tetras need?
At least 18 gallons (68 liters) for a group of 6. The smallest standard tank that works is the 20 gallon high. A bigger tank is always easier to keep stable. We give the size for an adult fish in a proper group, because the small fish in the shop will grow. Scientific name: Hemigrammus ocellifer.
How many head-and-tail-light tetras in each tank size?
This is how many each standard tank carries comfortably if head-and-tail-light tetras are the only fish in it. Share the tank with other species and the number goes down.
| Tank | How many head-and-tail-light tetras |
|---|---|
| 5 gallon | Too small |
| 10 gallon | Too small |
| 20 gallon long | up to 12 |
| 29 gallon | up to 18 |
| 40 gallon breeder | up to 25 |
| 55 gallon | up to 35 |
| 75 gallon | up to 47 |
| 125 gallon | 60 or more |
Check head-and-tail-light tetras against your own tank and other fish
Good to know
- Keep at least 6. Alone or in twos and threes, head-and-tail-light tetras hide, stop eating well, or pick on each other.
Tank mates for head-and-tail-light tetras
These animals like the same water, are a safe size, and have a temper that fits. It is a match on paper: always watch new tankmates for the first week.
- Marbled hatchetfish
- Sterba's corydoras
- Clown pleco
- Bloodfin tetra
- Dwarf chain loach
- Honey gourami
- Threadfin rainbowfish
- Croaking gourami
Poor matches
- Fancy goldfish: Goldfish do best with other fancy goldfish.
- Oscar: Oscar is aggressive and will bully or kill peaceful fish such as head-and-tail-light tetra.
- Molly: They need different water: Head-and-tail-light tetra likes a pH of 5.5–7.5, molly likes 7.5–8.5.
Questions and answers
What size tank do head-and-tail-light tetras need?
At least 18 gallons (68 liters) for a group of 6. The smallest standard tank that works is the 20 gallon high. A bigger tank is always easier to keep stable.
How many head-and-tail-light tetras should be kept together?
At least 6. Head-and-tail-light tetras are social animals and only behave naturally in a group. A group of 10 or more is better if the tank has room.
Can head-and-tail-light tetras live in a 10 gallon tank?
No. Head-and-tail-light tetra needs at least 18 gallons (68 liters).
What temperature do head-and-tail-light tetras need?
75–82 °F (24–28 °C), with a pH of 5.5–7.5. In most homes that means a heater.
Can head-and-tail-light tetras live with a betta?
Usually, yes, in a tank of 18 gallons (68 liters) or more. They like the same water: 75–82 °F (24–28 °C). Every betta has its own temper, so watch closely for the first week and have a spare tank ready.
More fish
Adult size, tank size and water ranges follow the mainstream care consensus (Seriously Fish species profiles and FishBase maximum lengths). Where sources differ we use the more cautious figure. Stocking numbers come from our stocking calculator.