temp question

Hello

i have a 20g long with a zoo med uth on the hot side and a smaller uth in the cool side both ran off lamp dimmers. Now the temps are 80 on the cool side and 91 on the warm side with the probed under aspen bedding and on top of reptiles carpet.but in the middle of the cage it is significantly cooler and i have the screen top taped off. So my question is is it OK for it to b cooler in the middle if it still has two spots to go to that are good temps

I would recommend cool side temps in the 78-80F range, and basking temps in the 88-90F range. You say the middle is cooler, but by how much?

What is the ambient air temp in the tank?
UTH do not heat the air and balls don't bask...............

my cool side is 78-80, hot side 90-93 and in the middle is 65-70. its in my basement and thats pretty much the room temp. and if i try a CHE the humidity goes away...but ive decided im just going to go with a 15 qt tub for now until i can get the tank figured out.