Double-check the temperature inside the tank with an IR temp gun, and just dial in the Herpstat setting to whatever it needs to be to get your actual ground temperature where you want it. Check under the substrate to make sure that part of the tank also isn't getting too hot. I'm still working on dialing in my settings to balance the ambient and ground temperature from my CHE. Also try to get the temperatures where you want them before putting your snek in there if possible.