oh yea...as i am looking at the pic of your setup....

you should get some water heater blanket and line the top of your lid underside.

right now its blue?

not much reflectivity there is it?

you can spray paint it white, but the water heater foil blanket is very refelctive and provides a layer of insulation so your plasstic roof doesnt melt like army men under a magnifying glass.

That was fun to do that wasnt it?

Hmmm.. maybe I will get me some army men too while i am at it