Angela, thanks for the tip on mite prevention. I tend to stretch my culture a little too long. It has bit me in the butt a few times and had to either drive the 1.5 hour round trip to Critter or ship cultures next day air (winter) from Josh Frogs.
I'll try to rotate my cultures quickly for a couple of months and see it they do away.
Mike,
I sometimes feel the itch after handling the cultures, I have always though it was a mental thing though. With regards to dusting the frogs, I agree with gsusfreak, if they look like snowmen then it is too much.
I find that if you put the cup at an angle and tap it rather than tip it, the flies will come out before the supplement. I use three supplements: calcium, vitamins and SuperPig. SuperPig is a color enhancer, now I haven't seen it make a difference but the frogs seem to eat these flies with more enthusiasm.