The short answer
A betta needs a heated, filtered, cycled tank of at least 19 litres (5 gallons), plus good food, a water conditioner and a test kit. Despite the myth of the bowl, bettas are tropical fish that only thrive in warm, clean, stable water — give them that and they’re one of the hardiest, most rewarding fish you can keep.
The betta checklist
- Tank — 19 litres or more. Bigger holds temperature better and is easier to keep clean.
- Heater — bettas need a steady 24–27 °C, so an aquarium heater is essential.
- Filter — a gentle filter keeps water clean; avoid strong flow, which tires their long fins.
- Food — a betta-specific pellet as a staple; browse fish food.
- Water conditioner and test kit — to dechlorinate tap water and monitor the cycle; see water testing.
- Lid, substrate and a few plants or hides to make them feel secure.
Why the heater and filter matter
Bettas come from warm, still tropical waters. Cold or fluctuating temperatures weaken their immune system, and an unfiltered tank lets ammonia build up fast. A heater and filter together give the warm, stable, low-waste environment that keeps a betta active, colourful and long-lived.
Setting it up
Cycle the tank before the betta goes in — running a fishless cycle means the beneficial bacteria are ready to handle waste from day one. See how to set up an aquarium and how to cycle an aquarium. Our best betta tank guide rounds up suitable setups, and the betta care sheet covers day-to-day care.