I know, I know, but I picked tanks because our home is so drafty. We also have two cats, so I wanted the rats to be more enclosed. I know now that cages would probably be better, but I just can't make that investment right now. (I'm too busy paying for tumor surgery-three down, two to go!) I am pretty meticulous about changing their bedding. They are litter trained, so that helps. I pick out the food they didn't eat and stir the tanks daily and wipe them down with every changing. In the summer, I have fans I clip to the top of the tanks to give them a little breeze, which they love. It's a lot of work, but they seem happy.
D