Thank you for the advice!

Yes, the overhead lamp is the only heating source I have; I have heard from a number of sources that UTH's are risky and not worth the hassle. I am having some trouble with the humidity, so I will try the cardboard idea and let you know how it goes.
Second pic is of the plexi cover I made and coated half with the foil tape and placed in on the top of the screen cover Really helps with humidity and holds heat in great.