Betta in a bowl: what a welfare study actually shows
The betta (Betta splendens) has long had a reputation for coping fine in a plain bowl, given its apparent lack of demands. A 2024 study published in the journal Animal Welfare compared the behaviour of male bettas rotated through five different housing volumes, from a 1.5-litre bowl to a furnished 19.3-litre tank (research on Google Scholar). Find our other setup pointers in the bedding and habitat section.
A study comparing bowl, small tank and large tank
Researchers moved the same fish through the five housing conditions and recorded their activity, resting time and the appearance of so-called "abnormal" behaviours: stereotyped swimming, repeated interaction with the glass, prolonged stillness at the surface. The finding is clear: in small, unfurnished volumes, these behaviours increase markedly compared with the largest tank.
What space and furnishings actually change
Volume alone is not enough: a large tank left bare produces more abnormal behaviours than a same-sized tank fitted with plants, hiding spots and substrate. Furnishings seem to matter as much as the litres available, offering visual landmarks and retreat zones. We cover this in our dedicated guide to setting up a 20-30 litre betta tank.
What volume to actually aim for
Based on these observations, the study recommends a minimum of 5.6 litres for display or sale in a pet shop, and a substantially larger volume for long-term keeping at home, always with gravel, plants and hiding spots. A bowl with no filter or heater meets none of these criteria and also makes water stability harder, an issue we detail in our guide to aquarium size for beginners.
Don't confuse apparent calm with welfare
A betta sitting still at the surface of a bowl is not necessarily "peaceful": that posture is actually among the behaviours linked to a poor environment in the study. By contrast, an active fish exploring a furnished tank, sometimes building a bubble nest or coming eagerly to feed, gives more reliable signs of good behavioural health, as noted in our guide to feeding a betta.
Frequently asked questions
Can a betta really live in a bowl?
It can survive there, but the available behavioural data show a clear advantage for larger, furnished volumes; without a proper filter and heater, a bowl remains a degraded setup.
What minimum volume should I aim for at home?
A tank of at least 20 litres, filtered, heated and planted, offers far more comfort and stability margin than a simple unequipped container.
Are hiding spots really useful?
Yes: they reduce the abnormal behaviours seen in bare tanks, even at equal volume, by giving the fish landmarks and retreat zones.
This guide is part of Planète Pets’s Fishkeeping universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.