I have kept corns for extended periods of time without additional heat. I kept the snake room above 80 during that time, but there were times it dropped to around 75. All of those snakes ate, pooped and grew normally. One of my friends keeps hers at room temperature. He's doing great. I don't think corns are as sensitive to temperature as more exotic snakes are. They are native to an area where the temperature fluctuates a lot. If you've ever been to VA it could snow one week, and the following week you are heading to the beach because its 80 degrees outside.