Jarred Betta fry

These Betta fish are a month old . they're still very tiny and so I've given them a smaller place to temporarily stay . as they grow I'll give them a bigger living space . but for now they will stay in these cups . mainly for them to learn how to flare better . usually Betta fish learn to flare faster in a smaller space .
they need to flare so they don't clamp their fins and be sick .