I jumped up from a 120 to 315 gallon tank this summer and have finally gotten around to getting a larger skimmer and am putting my Warner MF201 skimmer up for sale. I purchased it in August 2012. This skimmer did a great job on my 120 but is too small for my current system. Its rated up to 250 gallons but when I spoke with John Warner he thought the sweet spot was around 180 gallons. It has one internal Eden pump that pulls around 1100 l/h of air. Footprint is around 10 inches by 10 inches and is around 20 to 22 inches high. They skimmer is in very good shape and I cleaned it in vinegar/water every few months. I'm going to pull it an clean it later today and will post a picture. In the meantime here is an article on it. Asking $250.
http://reefbuilders.com/2011/08/16/warner-marine-mf201-skimmer/
http://reefbuilders.com/2011/08/16/warner-marine-mf201-skimmer/