Aqua Medic Temp controller

[mildcustom2]

I used to have a problem when I first got my Aquamedic temp controller with it reading a higher temp than what was in the tank, reverse of your problem. I discovered that it had to do with the positioning of the probe. It was in a low water flow area near the top of the tank. Metal halide lights were causing it to heat up. As it was I would get at least a 2* differential between tank temp and the set point before it would come on. Hope this helps.