Tubs are so much nicer for the bp. I do use some aquariums but i love the tubs. They are like 6-10 bucks at walgreens and target. If u live near a walmart prob less. he nice ones that have locking lids are like 10 at target and work great. otherwise ya criagslist might have somethin. i have a couple large ones i got for free so keep lookin around. Yard and garage sales are great 2