Quote Originally Posted by KMG View Post
10-15% of the snakes weight is a good guide.
I follow a similar rule until my snakes get older. But once they get past about 1000 grams I usually feed them medium rats from there on out. Even if I have to give them a second one I've begun to feel like bigger rats are just too risky, and most of mine will not take frozen/thawed. But that's just my personal rule.