Mmmkay where to start.
Lets start with 5 mommas and 1 inbred male. All the mothers can get pregnant 24 hours of giving birth, very very bad for them. If you don't separate the sexes of the rats by 5 weeks you will have A LOT more pregnant females. You could end up with 100's! If you don't have a lot of room in your cage that could be the reason that the one female is aggressive..they will fight if they are cramped. Here is a cage calculator...punch in your dimensions and it will tell you how many rats can comfortably (and be healthy) in your cage...
http://www.fancy-rats.co.uk/informat...agecalculator/
I noticed on another thread you said your rats had lice. Rats have very sensitive respiratory systems and those "fumes" could really damage their lung tissue...worst treatment ever IMO...probably pushed by the salespeople at petstores who sell salt wheels, etc to unsuspecting ratowners, and who know nothing about the care of rats! I use kitten Revolution, one drop and they are gone.