I have one Cinderella99/Northern Lights cross that has no odor, but my 3 NYCdiesel/SAGE/Cotton Candy are stinkers ... my girlfriend smelled them immediately upon entering the house, when they were just seedlings (I have a very poor sense of smell) ... after those two lights, she says she smells NOTHING, and they are now into flower ... I positioned them so the exhaust fan pulls the air past the ionizer bulbs, on the way out of the 2'x4'x7' cabinet ... I dont have as much ventilation as I would like, so that possibly helps them work better, since the air doesn't "rush" past them, giving them a moment to work .. ? .. just a theory ... :smokin: