Product review (3 stars): Tempermental but when it works this is excellent
This product worked well the first couple times I used it but after about 1 week the water stopped flowing through it and the humidifier thought it was empty and would stop running.  I had to remove the filter so that the water would flow into the main chamber.  This may have been a defect in the filter but it seemed that the cylinder that was suppose to push the spring up and let the water flow through the filter was not always engaged enough to allow the water to flow through.  However, when it did work it worked very well. I saw a noticiable different in the amount of white chalky dust in the room when the filter was working.