I wouldn't always go with the 10-15% feeding to there weight.. my normal was 303g jan 15th.. I feed him 18-22g adult mice every 5 days and on Feb 1st he weighed in at 352g so roughly 3 feedings and he gained 49g and yes empty weight as he left me a cat turd in there the day before.. so that 10-15% shud just be discarded if you ask me. At the 145g you stated adult mice from petsmart should be fine the weight is usally 18-23g also check this thread out its a very good read on the subject http://ball-pythons.net/forums/showt...r-Ball-Pythons