Screen treating with foil is easy: 3 layers of aluminum foil, shiny side down, topped/held on with duct tape. A hole is then cut on one side for ventilation/heat lamps. I add a vinyl 'window' in the center for light to get in as well. You can see it on the pix of the tanks above.
I made a photo step-by-step of the process when I did the screen to my ExoTerra. I can PM it to you if you'd like.
That would be awesome because I am a visual learner. Thanks!