I waited a good 2 months with the rats and never got babies... i dont know what i did wrong but it was frustrating! I'm having wonderful luck with my micies I think i will try rats again soon though.

On that note.... good luck with them! It wsounds like you have some promise with the nesting and all. Does she have a little pear shape tummy? It's hard to tell with rats sometimes, they dont get really big until about a week, even a few days, before they are going to pop. (when I had rats as pets i got babies, and didnt have the heart to feed them to my snakes... good timing huh)

I would clean the tubs ... and keep cleaning the tubs like you normally do even after babies come. The cage will get stinkier with all of those new bodies in there, and mom shouldn't mind too much if you move the family around a bit. Just do it quickly and gently and all should be well.