Bin the bowl: what a betta really needs
The single most damaging myth in the hobby is that bettas are happy in tiny unheated bowls. They are tropical fish from warm, still waters, and they need the same core kit as any other tropical fish: a properly sized tank, a heater and a filter. Give them that and a betta becomes a curious, interactive, long-lived pet with astonishing colours; deny it and you get a listless fish that fades within months.
Aim for a tank of at least 19 litres (5 gallons), and treat that as a floor rather than a target — bigger is more stable and more interesting. Our best betta tank picks are sized and equipped for exactly this, and the aquariums hub covers the wider range.
Heater: steady tropical warmth
A betta wants water held steadily around 25–27°C, and no room stays there on its own through the night and the seasons. A thermostatic heater is non-negotiable. Size it to your tank — roughly 1 watt per litre in a heated room — and pair it with a separate thermometer so you can trust the temperature. Our heater sizing guide walks through the details, and the heaters hub compares suitable models.
Filter, but keep the flow gentle
A filter keeps the water clean and drives the nitrogen cycle that processes waste — so yes, a betta tank needs one. The catch is flow. Bettas have long, heavy fins and are weak swimmers, so a strong current leaves them pinned to the glass and exhausted. Choose or adjust for gentle movement:
- A small sponge filter on a low air pump is ideal — effective and naturally gentle.
- If you use a hang-on or internal filter, baffle the outflow (a sponge over the nozzle, or a deflector) to soften the current.
- Watch the fish: if the betta struggles to hold position or its fins are constantly blown about, reduce the flow.
Always cycle the tank fully before adding your betta — this is what makes the water safe.
Plants, décor and a secure lid
Bettas love a densely furnished tank with places to rest and explore. Soft silk or live plants, a floating betta hammock near the surface, and some caves or driftwood all reduce stress and show off their behaviour — avoid hard plastic plants with sharp edges that tear delicate fins. Easy live plants like anubias and java fern are perfect; see the easiest plants for beginners and our planting guide.
A secure lid is essential. Bettas are determined jumpers, and they also breathe air at the surface through a labyrinth organ, so they need a warm air gap between the water and the lid — an open tank risks both a jumped fish and a chill on that vital air. See do I need a lid for more.
Settling your betta in
Once the cycled tank is warm and gently filtered, acclimate your betta slowly to match the temperature and water before releasing it. Feed a quality betta-specific food sparingly — they beg convincingly and overfeeding fouls the water — and keep up gentle weekly water changes. Get the fundamentals right and a well-kept betta will reward you with years of colour and personality. For the full build order, our tank set-up guide covers every step.