I've always heated rat up to over 100. At first I was trying to feed every 5 days then increased to 10. I just think its weird he only has ate the 2 rats I bought from a pet store. I've had him 8 weeks. I also bought a 10 medium frozen from the breeder and gave them to a friend since its going to be awhile before mine can eat them and my friend just called me and told me his ball refused the ones I gave him but ate one he still had. Coincidence?