Half toe missing & Bleeding

Question
I have a rat named Chip she is all white I got her maybe 4 months ago she was a fat rat but I then got her a Rommate and the little rat Snow picked on her and made her bleed a lot. they are now separated but Chip this morning somehow ripped off half her toe nail and I am having trouble stopping the bleeding. I was told corn starch but all i have was flour and baby powder. It has stopped a little but she lickers it and no vet here will see her. What else can I do.
the rest of the information you ask for is
she has not been altered, her bedding is soft sorbent colors and I got her from a pet store. She was in a small plastic drawer with one other rat. I decided to buy her to get her out of those conditions a few months later the rats are in a big fishtank together  with lots of food and toys. she is out often with us. we take her out to the stores as well.

Answer
If you know beyond a doubt that the other rat did it, I suggest perhaps getting her a less aggressive roommate. As for toe wounds, clean it up and then leave it alone. Toes heal very quickly and will do so on their own. Don't worry about it unless half of her foot is missing.