so i noticed that every morning when i would wake up i would see all of the sub strait would be dug out all the way to the bottom of the tank. I didnt know what was going on till last night i looked in and saw him like burrowing in it... is this bad or does it mean anything... my temps are good around 88-91 on the hot side about 82 on the cool side and an ambient temp of about 79.... he is kept in a vivarium with a undertank heater on his hot side but also a heat lamp over top on the cooler days... humidity about 45%