You really have to tweak the intake valve until you get it right. Just start with it fully open and then back off until the water drops just below the o-ring in the throat.....let it run and increase or decrease in small increments about every half an hour until you get. Also, it took two weeks for my prism to break in and begin to skim efficiently. Specific gravity also will affect skimming. The foam will collect over time and wont just foam into the cup like when you pour a beer to fast and it foams over. I empty mine about every two or three days, but I only skim for 8 hours each day as I worry about overflow if I am asleep.
