My snake doesn't burrow at all so won't putting the probe on the glass be an inaccurate reading? Even though it is only an inch or so depth the heat diffuses through the substrate so it is cooler right on the top then right on the bottom. I don't want you to think I am calling you wrong, it just doesn't make sence to me. Why would you want a temp reading that is going to be higher then the temp the snake is actually getting?