Quote Originally Posted by craigafrechette View Post
Snake's can and will burrow, push substrate around and lay directly on the glass. So you want your actual glass surface no hotter than 90. I go 88-89. So you'll want to adjust yoyr tstat to whatever is requiredto achieve those temps.

As for the probe placement, always OUTSIDE. They can and will be moved, peed on, etc...which can cause inaccurate readings and potential heat spikes. These heat spikes can be dangerous and even fatal.
I've heard this about probe placement as well, unfortunately I can't put the probe between the heat mat at the moment as it's already applied and removing it is not recommended from what I've seen. I check probe placement constantly to ensure it hasn't moved, in the future I'll definitely look to fix this.