Newts, I have found that if you keep the input tube (and the airline tubing) clean it doesnt collect air bubbles in it as much. As i said in my first post, I called Redsea and the lady i spoke to said about once a month take the skimmer apart and soak it in a bucket of hot water with 1-2 cups of vinegar (i use white vinegar) for an hour or so.. it will loosen all the buildup inside the skimmer, to make it more efficient. I usually run a pipe cleaner though the airline tubes and the input tube.
For all you non-believers out there, I realize that i could have purchased a better skimmer, but for my tank its perfect (29gal) and with the addition of the surface skimmer, its even better.
Freedom75, If yours LFS doesnt stock them or cant order them (they were just released this month) I can give you the # for the shop her that has them in stock if you like. It cost me 35.00, but i see it as well worth it