They are very cute! Good luck with your project. Breeding rats is actually fun for me.
Why bother with a glass tank when you can easily make some bin out of Rubbermaid tubs? With the Rubbermaid tubs you can always have a clean one ready and they are much lighter than a glass tank. I've never kept rats in glass tanks, am I missing something?
There are several post on how to make the tubs.