ok thanks, i did raise the tank alittle with a fan blowing on it but it still needs frozen water bottles to keep the water below 70. i'm using 2 bottles at a time now and am able to keep the water temp below 70 for 3 or 4 hours at a time. i ordered one of those ice probe chillers but it's on backorder, also i put the water pump on a timer to cycle an hour on and off