Product review (3 stars): changing often in baby's room
I agree with R. Myers comments about lack of information on how often to change the filter or prolong the life of the filter. We have a Graco humidifier in our son's room that uses these filters. My wife wants to replace the filter when she begins to smell an odor being emitted from the humidifier. Sure enough, the filter has begun to turn brown when she smells the odor. Amazon was the only site where we were able to find these replacement filters. Thank you, Amazon!