Betta: Tank Size, Tank Mates and Setup
A colourful, personable fish that does best alone or with calm tank mates in a heated, filtered tank of 5 gallons or more.
- Minimum tank
- 5 gallons
- Temperature
- 76–82°F
- Group size
- One per tank
- Adult size
- 2.5 inTop of the tank
- Needs a heater. Bettas are tropical and become sluggish below about 76°F.
- Prefers gentle flow; a sponge filter or a baffled filter works well.
- Breathes air at the surface, so leave a gap under the lid.
Betta splendens. Figures are commonly published care ranges; see how it works.
How many bettas per tank size
The most you could keep if bettas were the only species. Open a size in the builder to add tank mates.
| Tank | Betta, kept alone | |
|---|---|---|
| 5 gallon | Up to 1 | Plan this tank |
| 10 gallon | Up to 1 | Plan this tank |
| 20 gallon | Up to 1 | Plan this tank |
| 29 gallon | Up to 1 | Plan this tank |
| 40 gallon | Up to 1 | Plan this tank |
| 55 gallon | Up to 1 | Plan this tank |
| 75 gallon | Up to 1 | Plan this tank |
What you need for a betta in a 5-gallon tank
A starting setup: 1 betta in the smallest standard tank that suits them.
5-gallon tank
- These fit a 5-gallon tank and get along. Aim for about 79°F.
Equipment, sized for this tank
Starter supplies
Paid links. As an Amazon Associate, TankStarter earns from qualifying purchases. Sizes are estimates from published care guidelines, not hands-on testing.
Betta tank mates
These share a temperature range and temperament with bettas, with no warnings from our checks.
Use caution with: black skirt tetra, white cloud minnow, tiger barb, dwarf gourami, fancy goldfish, cherry shrimp, amano shrimp. Add them in the builder to see why.
Plan a tank around bettas
Add tank mates, check the stocking level and get the equipment sized for your tank.
Open the tank builderBetta questions
What size tank does a betta need?
At least 5 gallons. A larger tank is more stable and gives you more choice of tank mates.
How many bettas can I keep in a 5-gallon tank?
Up to about 1 if they are the only species in the tank. Male bettas fight, so keep one per tank.
Do bettas need a heater?
Usually yes. Betta does best at 76–82°F, which is warmer than most rooms. A 5-gallon tank needs about 50 watts in a 68°F room.
What fish can live with bettas?
Good matches include neon tetras, cardinal tetras, ember tetras, rummy-nose tetras, guppies, Endler's livebearers. They share a temperature range and temperament with bettas.