I think a 75 watt bulb in a 10 gal is way to hot. I have a 60 watt and its too hot. I think a 50 watt would be best you should buy a heat pad and put it under their maybe that would be better. I suggest you cover the sceen so you can get your humidity up a little. I cover some of my tank cages with aluminum foil it helps hold humidity.
Hope I helped.