I use a heat lamp for one of my enclosures and it's fine as long as you mist the cage regularly. I'm using a black lightbulb so i can keep it on 24/7 without a problem. There is also ceramic heat emitters which gives off no light whatsoever but you need to use it with a ceramic light fixture so if you don't already have one, I'd suggest a black light. Humidity will be a problem with any light you choose, but misting works fine for me.