These are used by breeders for jarring males or you could use them for isolating female in spawning tank before release or for taking photos in. Def not a longterm solution especially for an adult betta
That looks so cruel im new to this whole fish lark and even i can see that a fish cant be hapy in that my goldies have complained in an 8L until i've moved them to a bigger home how could the fish be happy in that???