V2 Skim 120 Nano Skimmer overskimming?

[dgoulston]

I have a V2 Skim 120 Nano Skimmer and for the last 2 months it has been producing about 1inch of skim every 4/5 nights.
but for the last 3 nights is has been producing about a cupful (4inch) of mainly dirty looking water)

is this normal? or is it playing up?

Darren

[cocoa_pleco]

is there any way to turn down the flow to get a more concentrated skim?