Hm, well maybe my questions might apply to any protein skimmer.
Well, I bought a Prizm, read all the instructions, set it up, and now i'm not sure if it's doing what it is supposed to. Foam enters the collection cup, bubbles pop leaving water which eventually completely fills the cup. I've been adjusting the flow rate with no success. In the end, the water leaks out back into the tank every so often.
you need the foam that enters the collection cup to be 'dry'. that means brown and sticky looking not wet and watery.
Id suggest that the water level in the riser tube is too high and you could try turning down the water flow to the skimmer. The slower the water flows through the skimmer the more it grabs at a time... So try adding a tap to close the pump down a bit.. if its brand new it may be in its breakin period which can last a couple of weeks...
...also, some types of water conditioner cause skimmers to do that, so if you have a new tank with treated water it may not work properly.
that is the main problem with skimmers from that price bracket... they are often hard to set up initially but once they get going are fine.. the same is said about seaclones which are a pain to set up and get running!
Its just a matter of playing with the air and water flow until you get the right balance...