Product review (5 stars): Works for about 3 weeks, then gets funky
I can't ding the product for my water supply. I have hard water, and my 10-gallon humidifier gets this water. It's not worth trying to use my kitchen water purifier to get soft water.

Anyway, this product works as described. I always buy them in bulk, as I don't know when the filters gets that musty smell and have to be replaced. Again, not the fault of the product - just don't use them with hard water.