Minimum tank size
Most fishkeeping groups recommend at least 5 gallons (about 19 litres) for one betta, with 10 gallons even better. Bigger tanks keep temperature and water quality stable, which matters more than swimming space alone. A 1 to 2 gallon bowl can't hold a heater and filter properly and swings in temperature and ammonia quickly.
What the tank needs
- Heater: bettas are tropical. Keep the water at 76 to 82°F (24 to 28°C).
- Gentle filter: a sponge filter or a filter with adjustable flow; long fins struggle in strong currents.
- Lid: bettas can jump.
- Plants and hiding spots: live or silk plants, and a leaf or log near the surface for resting. Avoid sharp plastic plants that tear fins.
- A cycled tank: follow our nitrogen cycle guide before adding your betta.
Water and maintenance
pH around 6.5 to 7.5, zero ammonia and nitrite, nitrate under about 20 ppm. Change 20 to 30% of the water weekly with dechlorinated, temperature-matched water. Feed a small amount of betta pellets once or twice a day; overfeeding is the most common problem.
Tank mates
Male bettas must never share a tank with another male. In 10 gallons or more, some bettas tolerate peaceful companions such as nerite snails, ember tetras or corydoras (in larger tanks), but every betta's temperament differs, so have a backup plan. Check numbers with the stocking calculator or the 5 gallon guide.
Frequently asked questions
Can a betta live in a bowl?
It can survive for a while, but not thrive. Unheated, unfiltered bowls shorten bettas’ lives and cause fin rot and stress.
How long do betta fish live?
Around 3 to 5 years with good care in a heated, filtered tank.