When you say "sucks the skimmer dry" do you mean that it pulls all the water out of the skimmer and sucks air in as well causing the loss of prime? If so, is your weir door (flapper in skimmer) working properly and/or is your pool water level low? Either of these could cause you to suck air in your skimmer and lose prime.
I doubt it's the filter work as it's on the pressure side.