I feed 30 gram rats to 2000 gram snakes quite often and they grow very well.
Eating every 4th day or so should give you 7-8 meals a month totaling 200+ grams a month intake and 50-70 grams a month weight gain.
I try for 75 - 100 grams a month weight gain but of course not all females co-operate.
In my experience big meals tend to throw them off feed or slow them down.