I think if you have an abnormally large BP, a 41 qt would be better. I have heard BP's equated to a pet rock. They barely move. I would personally use 32 qts for all of mine just because I think the 41 qts are just too big and awkward and I just don't like them because of their length. However, if you plan on breeding babies, the 32 qts would be too large for the babies/juvies. I would buy Iris tubs if you can. They are just really straight forward and they have good prices. I use the smallest tubs, I think they are about 8 qts for babies. Then for juvies I use the 12.2 qt. Then for subadults/adults I use the CB-70's or the sterilite 32 qts. I hope that helped you and good luck on your rack. 