Okay let me first explain that I am no expert on the subject, but I have several breeding cages set up. In my opinion glass cages or aquariums work best as far as I asm concerned for two reasons. First off you dont have to change the bedding as often and the general health of my glass caged mice seem better. For my other cages I used the plastic sterilite cages as well. I recommend that you cut the center of the top out and put mesh wire in the center (duct tape holds well) because it gets intirely too humid inside of the cages with just holes punched in it. Even with the mesh wire tops I still have to change the bedding every 3 or 4 days compared to my glass cages once a week. In my breeder cages I put one male with 4 females and leave them be, except to feed and water daily. I have also learned that it is best to mark your male (i used a blue highlighter) if the mice are all white, just in case they dont breed well. Best to start with medium size mice. Older mice dont breed as good and have less pups. I also have a community cage that I keep feeders in so I dont have to take any out of my breeder cages. Also something I would say is very important. Try to keep males (adult) in seperate cages, because with females present they will fight, and most likely kill the weeker younger males. If they are raised together (siblings) they will be fine. Sorry this was so long, but I got carried away. If you need any more advise, just ask.