ok, so I woke up this morning to temp problems and I cannot decide what's going on. I thought I had it stable but suddenly I get up this morning and it is 96 on the floor of the hot side when I moved substrate aside and measured with a temp gun, the digital readout on the thermostat is 93, and I have it set to 90. Light is off on the thermostat so supposedly not heating. Astrid was out in the tub. I moved her hot hide so that it was just off the heat so she wouldn't be harmed. I have the probe for the thermostat (jump start type) between the heat mat and the bottom of the tub. It is a Flukers heat mat and I have the probe fully on the black part of the mat that heats. I don't get what's going on. Do you guys think I have an equipment failure or could it be a setup issue?

I went ahead and ordered some flexwatt (they will be wiring) and a herpstat ez1. I was planning to eventually get one anyway, when I got ready to move her to a bigger enclosure. Any suggestions on what to do in the meantime? I have another heat mat I can try, but unfortunately I don't have a spare thermostat or anywhere locally that sells them. Could I try a lamp dimmer switch, or can you use those with heat mats?