i dont quite understand what your saying here. but what i am getting is that you think a snake will stop growing due to the size of the enclosure and then die? a snakes growth has nothing to do with its inclosure, its what your feeding and how much, its a health thing. if you are feeding your adult snake two big mice a week but you have it in a 5 gallon tank its not just gonna roll over dead. but i would say it could cause some extreme stress to the snake which could lead to eating problems then cause death but thats not because it has stopped growing, its because it stopped eating. or your snake might just get really fat from sitting in a 5 gallon and eating fat mice every week, lol.