You can get ceramic heat emitters and leave them on all the time. They are more expensive that bulbs but last longer as well. BPs are nocturnal so don't need a lot of light. The light is more for viewing purposes. The ambient light you get from a window or the house lights will work. As you've already acknowledged this is just a hard set up to deal with. I know because I have a 40 gal tank with screen top as well. I will be odering my t-8 from animal plastics soon, and am hopeful that will cure a lot of my headaches as far as husbandry goes. Not sure how you are doing with humidity. I cover most of my screen with damp towels for that purpose as much or more than for holding in heat. Good luck with everything. It takes some tinkinering but I'm sure you'll find the combo that works. It's just a headache and high maintenance.