I went the cheap version and got a $5 aquarium pump from wal mart and stuck some weather stripping foam on the bottom. Cut 6 slots in it for it to sit on the strings. I'm not sold that it did anything but it was a cheap experiment. I only ran it for about a week at a time. Maybe longer would do more, who knows. There's no way I would pay what Tonerite wants for one without any proof of results though.