I'm going through the same thing though mine are much younger. I started mine out on f/t mice then picked up 3 new hatchlings and two of them would only eat live so I started buying live mice from a local breeder but having 40 mice in the house/garage smelled awful so I decided to switch them back. However, I decided to switch to f/t rats as well and so far about half my collection has taken to the rats no problem, the others have been eating the last of my frozen mice and I broke down and bought two feeder mice the other day at Petco for my two picky eaters. I'm hopeful that as they get bigger they will make the switch to f/t rats.