You want to feed a rodent that is as big around as the thickest part of the snake. If it was eating frozen/thawed the feed it that but make sure it is thawed properly and is the right size. If it was eating live then feed live and never leave a snake unattended with a live rodent. If you can get the appropriate sized rat feed rats, if not you will have to feed mice.
What are you using as heat source? What are you using to take temps? How are you regulating your heat source?
Congrats on the new snake! Welcome to the forum! I recommend reading this care sheet even if you have read other care sheets. Here is the link.
http://ball-pythons.net/forums/showt...ius)-Caresheet http://ball-pythons.net/forums/showt...ius)-Caresheet
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