Some thoughts :]

1. Infra-red can't cause any kind of problems in their behavior, and/or eye's. I've been looking for information on it and can't find anything. I've always been under the idea that infra-red bulb's can be on as a 24 hour heat source. If you got anything saying otherwise please send my way, I just never found anything.

2. Saran wrap, and foil are good quick fixes but try plexi. It seems you guys are worried about it catching fire so why mess with it? Plexi is cheap, and is an end-all for humidity issues. Back in the day my pops used to hate when I used saran wrap because he thought I would burn the house down too lol. He made me use plexi, and honestly it's so much better. It looks nicer, and doesn't pose any kind of hazard. It's also cool because it's perfectly see through, and you don't loose any kind of sight from the top of the tank. If you use it to cover up 2/3's and then cut a hole in the center of that piece it works beautifully.

3. Forgot to mention to use a probe WHENEVER using any kind of heat lamp. I usually just leave the probe in the tank before I put any animal in a tank with a lamp. Accurite has a really cheap thermometer/hygrometer. It will record Ambient temps, humidity, and probe temps. It costs 12 bucks at walmart. I have like 10 of them for my snakes lol. But you put the probe on the substrate directly below the lamp, and see what it gets to. I can link you guys if you want.