I just purchased this 120g skimmer for my tank. I have a very limited amount of space in my sump and no room for a hob skimmer. My question - has anyone else installed one of these? I cannot get it to function correctly (or my perception of correctly) I have adjusted the water lever and it just continues to flow water over and out of the top of the cup. I know there is a breaking period but is this part of the breakin period? Please advise