I have a somewhat cold house in the winter and on the cool side I use a Zilla Mini Halogen heat light, they have 25 and 50 w day and night bulbs, I'd suggest the 25w red night bulb and just keep it on all the time that should get you into the 70's unless your house is really cold, I also use a UTH and ceramic heat emitter on the warm side with a thermostat, seems to work out well for me but with all the heaters it takes a little more to get the humidity up but I can get it right at 40-45% with just a damp towel covering 2/3 of the top (with a hole cut for my heat light) and then I mist during sheds to get it higher.