Some of the old Brit engineers who turned me onto tubes when I was in college used to say, "The best way to clean your discs is to play them", unfortunately that just doesn't quite do it for me. They always had some axiom or another. One I have always liked, "If your gear is worth more than your music, you have it arse backwards". I zap my discs with my zerostat and brush everytime I play them, dust and low humidity is horrible here.
Cheers,
Shawn