I apologize now for long winded story. I have started a beetle colony and it's doing great.. I am currently keeping them in a tote with heater and ventilated. And am in the process of converting a deep freezer. As for decreasing them I did my first successful one on the stove. Worked great but don't want to do them in my kitchen. I now got a heavy duty tote. A hot water heater element and a thermostat from Home depot. Once all together and wired and running the water is getting hotter than setting on it. I set at 120 and it was at 180 when I shut it off. I am fairly mechanical. I wondered how temp control worked. There are no temp leads. To the tank. No provisions on thermostat . What am I not seeing? Thanks.