I think your plan will be fine.
I have done one appropriately sized food item every 5 days, or 7 days, and honestly, have not had different results.
Since each snake is an individual, your bull snake's metabolism may be faster or slower than others. I pay attention to their weight, and if they are a little thinner than normal before next feeding, I feed them. Or, if not, wait until the next planned time.
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Genesis 1:1


