I bought an Indoor/Outdoor thermometer yesterday, and without even thinking , I put the sensor inside the tank, I figured since it was for outdoor use it must be sealed well. Everything seemed to working fine last night, but now the outdoor temp (tank water) is reading about 5 deg. higher than yesterday with the MH on. I removed the sensor from the tank and it still reads about 10 higher that the room temp. Im thinking that even though it was designed for outdoor use, probably not that kind of saturation. My question is how acurate would it be to get another thermometer and stick the sensor to the outside of the glass. I have a stick-on strip thermoter now and have wondered how acurate it really was.