i've two bettas in kritter keepers, one in a sterilite bin, and one in a bowl(Lulu. cause she hates anything bigger than a gallon. odd girl. :/). Chappy's in an actual tank, Caroline's in an actual tank, and Theo's in an actual tank, and his is the only glass one. xD
i think, they're so addicting, because they're like little people. they've so much personality, it's hard to NOT become attached to them! then, you want more, to see more of that human-like personality. the fact that no two act alike, is really amazing, too! out of seven, they all act different!