First of all, 80 should be ambient temp, he needs a hot side with temps of 90. It is also very common for ball pythons to go on food strike, and going for a year is not unheard of. If he is cold, he may not eat because he can't digest without proper temps. Get his temps up, make sure he has secure snug hides, and leave him alone. Let him settle in. You may try live food to jump start his interest. Do you have pictures of him? Also, the 50, or 55 what ever it was, is too big for him and not necessary.
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