What size tank does a betta need?
At least 5 gallons (19 liters). The smallest standard tank that works is the 5 gallon. A bigger tank is always easier to keep stable. We give the size for an adult fish, because the small fish in the shop will grow. Scientific name: Betta splendens.
How many bettas in each tank size?
This is how many each standard tank carries comfortably if bettas are the only fish in it. Share the tank with other species and the number goes down.
Keep one betta per tank, whatever the size. Of the common sizes, these are big enough: 5 gallon, 10 gallon, 20 gallon long, 29 gallon, 40 gallon breeder, 55 gallon, 75 gallon, 125 gallon.
Check bettas against your own tank and other fish
Good to know
- One male per tank. A heater and a gentle filter are needed.
- Its long fins are a target. Avoid fin-nippers such as tiger barbs and serpae tetras.
Tank mates for bettas
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.
- Chili rasbora
- Ember tetra
- Cherry shrimp
- Nerite snail
- Cardinal tetra
- Glowlight tetra
- Black neon tetra
- Rummy-nose tetra
Poor matches
- Guppy: Betta often attacks other fish with long, flowing fins, such as guppy.
- Fancy goldfish: Goldfish do best with other fancy goldfish.
- Tiger barb: Tiger barb nips fins and betta has long fins. Avoid this pair.
- Oscar: Oscar (about 12 in) can eat betta (about 2.6 in).
Can bettas live with...
- guppies
- neon tetras
- fancy goldfish
- angelfish
- bronze corydoras
- mollies
- platies
- tiger barbs
- dwarf gouramis
- cherry shrimp
- oscars
- zebra danios
- bristlenose plecos
Questions and answers
What size tank does a betta need?
At least 5 gallons (19 liters). The smallest standard tank that works is the 5 gallon. A bigger tank is always easier to keep stable.
How many bettas should be kept together?
One male per tank. Males fight each other, often to the death.
Can bettas live in a 10 gallon tank?
Yes. One betta does well in a 10 gallon tank.
What temperature do bettas need?
75–82 °F (24–28 °C), with a pH of 6–7.8. In most homes that means a heater.
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.