I'm having these issues right now. I'm averaging 85F. I put a frozen gatorade bottle and it dropped by about 5 degrees only.

I would spend the money on a chiller...but how could this work for my power cloner? There's no additional holes available on the res to do the circulation. I guess I could cut my own, but I'd probably f that up some how.

I guess I'll be getting more gatorade bottles...

Despite the high temp, my clones are still rooting.