Just happened to place my hand on my mom's nano reef tonight and the glass felt really warm. So I checked the won pro II heater and it was stilled dialed in at 80F. I spun the dial and it clicked on and off so the heater wasn't jammed on. I went and got a thermometer and the temp was a little over 90, here clown was acting a little funny as well but it was after lights out so I think he was sleepy as well(hoping) Anyway what happened was the little suction cup thermometer with the heater apparently came off the glass and popped out of the water. Since the temperature in the house is below 80F the heater just stayed on heating up the water more and more. It's lucky I happened to find because by morning I'm sure everything would have been dead.