skimmer setup secrets?

[Graham_f]

I have been using my Eshopps psk 100 for about a year now, i can never seem to get it to function great. Its always a super wet skim (like 5 gallon bucket a week!) or so dry nothing really makes it into the collection cup, it just sticks to the top of the bubble tube.

its sitting in a stable 9" of water, Ive replaced the pump due to a malfunction about 3 months ago. Its cleaned monthly and the collection cup is emptied once a week...or by the hour when its acting up
Its to the point that i have overflow buckets setup in case it freaks out while i'm at work and more than a few times i have come home to them full and my tank salinity way out of wack due to the ato working overtime.

there seems to be no middle ground. A extremely small adjustment one way or another make it pretty much useless. I know its not a fancy skimmer... am i just expecting too much for this piece of junk?

any secrets? I'm sure my corals would appreciate a little clean stable water for once