Product review (4 stars): SUCK UP WATER
THESE FILTERS SUCK UP WATER SO THE FAN CAN BLOW MOISTURE INTO THE AIR.  THEY WORK WELL FOR THAT PURPOSE, BUT AFTER PROLONGED USE THE MINERALS IN THE WATER HARDENS THE ELEMENT AND WATER IS NOT DRAWN UP INTO THE FILTER SO WELL.  THAT IS NOT THE MATERIAL'S FAULT, JUST THE WAY IT IS.