🏠The Betta tank: 20 L, hardware and start-up
Betta : A tank of 20 L or more, densely planted, with almost no current and a clear surface for breathing. A lid is mandatory and water height should stay moderate so it can reach the surface easily.
In short: 6 to 7 cm as an adult, 20 L minimum for a single male, heated water between 24 and 27 °C. Spectacularly territorial: two males together means a guaranteed fight — hence the name fighting fish. A labyrinth fish that breathes air at the surface: the tank needs a lid (it jumps) and gentle flow — those long fins tire quickly.
20 litres minimum: why that number
For a Betta reaching 6 cm as an adult, plan 20 real litres — and remember a big tank is more STABLE, hence easier, than a small one: parameters drift slowly, leaving time to correct. This volume suits a sturdy standard cabinet — just verify perfect levelness.
Hardware: filter, heater, lighting
A filter turning the volume over three to five times an hour, with the outflow broken against the glass — those fins cannot fight strong current, a heater around 1 W per litre set to 24 to 28°C, backed by an independent thermometer — built-in thermostats sometimes lie, and lighting on a timer at 8 to 10 hours a day: any longer and the algae win.
Substrate, plants and start-up
Nutrient substrate under fine sand or quartz, robust plants (anubias, vallisneria, Java moss) and wood to structure the territory. Then patience: a complete nitrogen cycle (3 to 4 weeks, nitrites back to zero) before the first Betta — the step every hurried beginner pays for dearly.
Frequently asked questions
What tank size for a Betta?
A real 20 litres minimum — below that, parameters drift too fast to catch.
Does a Betta need a heater?
Yes, about 1 W per litre set to 24 to 28°C, with an independent thermometer double-checking the thermostat.
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