Begin with your stand pipe high enough for some foaming to collect in the cup and keep a close eye from there.... as it "breaks in" you'll find that you'll need to bring the stand pipe down as the foam in the collection cup becomes too wet. BTW, I advise running the skimmer in the bathtub(hot water) for an hour or so to help clean out any shipping/manufacturing oils, etc... break in time may be accelerated.

Jason