An adult can take rats. So it'll need feeding every 2-3 weeks when on rats. Every week if you use mice. 6 week periods is practically staving it. I'm not suprised it has not hit 3 feet yet. If that snake were properly fed it'd be 40+ inches long as fat. Good thing it is in your hands. Try rats, see if it will take them. Maybe it is too late to switch.