5 gallon buckets. As long as they are healthy and thriving. I am in the process of going back to smaller cages. IMHO, they do better and are much easier to maintain. I had more success breeding them in racks and 24x24x16 cages....with light bulbs for heat.lol. I'm switching back to racks now with Sterlite 76 qt. tubs. I think they measure 16X23x15 or close to it. Choose what works best for you and your animals.