I need to work on the Hot Spot also... Right now we're just going to worry about the ambient.. We have the hot side/cool side pretty much under control.. Probably going to have to switch to the Flucker mini UTH.. The one for 10-20 gal. tanks takes up about 2/3 of the bottom.. So are difference in temps are only about 5 degrees from Hot hide to Cool Hide.. That was checked with a PE 2 heat gun.