Exactly as Jessica said because beardies sense heat from the 3rd eye on top of their head so if the heater gets too hot, they could get burned very badly.
I added an 75W infrared to my daytime lighting schema to kick the cool side temp up from 70 to 80 without making it too much brighter in there. You could also consider adding a CHE (Ceramic Heat Emitter) to increase the ambient temperature.
I also have a regular 75 watt day light bulb to heat my cool side, a 75 watt basking bulb and a zilla UVB(waiting for my reptisun to be delivered!) and my temps are pretty good.
Kay this is weird he is spending all his time on the cool side that's only at 70 right now lol even I moved the baskin light over and he moved.. I'm wondering if I need to buy a reptisun 10.0
I added an 75W infrared to my daytime lighting schema to kick the cool side temp up from 70 to 80 without making it too much brighter in there. You could also consider adding a CHE (Ceramic Heat Emitter) to increase the ambient temperature.
I believe dragons love it bright, the brighter the tank the happier the dragon. I could be wrong but that it what i have read. I believe the red light may actually bother their eyes.