The fan, Jack , is not to cool the bloody bugs, it's to prevent them from landing or flying around. You need to think outside the box -You might use a fan for "cooling", but what fans primarily do is move air and moving air with more energy than those flies can fly against or stand up to is the sole reason I had for suggesting the use of a fan. The movement of the air will act like a strong rip tide to drive the flies from their desired source of food. And that IMO is what is "cool" about using a fan in this context. (Now I understand your reference to dry ice... fan = cooling , rather than fan = moving air). But if my idea is "silly" I will happily and proudly wear that badge.