sorry guys - it is 82f (was in a hurry when I wrote the quastion) I have already lowered the temp on the heater to 70f (heater is working fine) also tried semi-cold small water changes (and ice thanks mypapercuthurts) and I can't have a fan blowing directly on to the the water as I have a few elephan noses in the tank which have a habbit of jumping through any gaps they can find. Thanks for the assistance any way guys, I was just hoping that there was something out there for keeping a tank at a constant temp in this heat we are having.