Product review (2 stars): Why is it so hard to get a good humidifier filter?
I tried this filter because, like others, I was disappointed that Honeywell started making thinner filters. However, this filter only have me about 1/3 of the lifetime, even compared to the thinner Honeywell filters. It just got clogged up and I could not wash out the junk.

My water is slightly hard, but not that bad. (Boston area municipal water supply) The other filters don't clog up so quickly.