A 6 footer may never be needed at all. I perosnally use the 4x2's or large tubs for all "dwarf" local and males. Heating woudl be the same half hot half not. It all depends on your feeding regime. If you feed once a 7 days the animal will be bigger then if you feed every 10 days or smaller yet at 2 weeks.. I mix it up, once a week, then to 10 days then to 7 days again and then 2 weeks bak to one week