Plexiglass?

[imitha]

You can cover the whole top with plexi or lexan if you want. Just drill a few holes on each side to give it an air current(hot air rises and cold air sinks so cold air comes in from the cold side holes and goes across the floor and then rises out of the cage via the warm side air holes). I would start with just a few holes and then add as needed to reach the desired humidity. Of course if you are cutting a hole to fit a dome, then skip the warm side holes and just cut the dome hole about 1/4 to 1/2" larger than the dome. That will double as the warm side vent.

I'm using uth so I don't have to worry about that. So should I cover the entire screen top then and drill some holes? And also will the patch of screen on the side of one of my cages defeat the purpose