To tell you the truth i don't know...if it looks overweight i would feed it every 3 weeks. Usually, you can tell if the snake is doing OK if they don't feel bony and have nice hard body I think then you'd know you are feeding it well and it's getting enough food. Many snake experts feed their snakes every 3 to 6 weeks and they still have nice firm plump bodies. They need very little to get by compared to mamals and birds, which burn tons of calories to keep a high constant body temperature. However, Herbivorous reptiles eat a lot because plant matter is very hard to digest and they don't get enough nutrients by eating small quantity, so they need to eat more than carnivorous or omnivorous reptiles. Some snakes can go for one whole year without eating and show no sign of irreversible damage, and ball python is one of them. But this should not be attempted. They have very low metabolism and very efficient digestive enzymes that can digest almost everything, bones, hair, and all. These are amazingly efficient animals designed very well for what they do to survive.