Product review (2 stars): Filter has not held up to previous reliability, as if outdated
Blue flakes formed in excess water beginning with second cleaning process within a two and a half week period (a pattern of three consecutive nights on, two days without use of humidifier throughout the 2 1/2 week period). Never happened during the previous two years of performance.  Purchased two filters: Preparing to use second filter much sooner than expected (filters are advertised to be used for to two months with normal use).  Hopefully, the second filter will meet with previous satisfaction, and only one refund will need to be requested.