"... Not much collects in the cup, but the entire neck would be filthy and make me gag every time I would clean it.[/quote]

O.K. I keep seeing pictures of other skimmers with thick foam by the cup-load and have been pulling my hair out trying to get the same result from mine. The neck on mine gets coated with dark-green muck as well. I usually have to use a rag to clean it out.