Just to make sure you are getting what bcr229 and I are saying, it seems to be getting lost in all tve other junk. You need a thermoSTAT to control the temp of your heat mat, My opinion is you should also have one to control the temp of the lamp. The thermoMETER will only tell you the temp and you need one to measure the surface temp on your heatmat. Somewhere on here is a geat write up on how to setup up a glass tank, search that out and read through it, good info.