Review on 16-Pack NANE Demineralization Cartridge for HoMedics Ultrasonic Humidifiers - Filter Mineral Deposits, Prevent Hard Water Build-Up, Purify Water, Eliminate White Dust and Odor by Mike Hamelin

I have them in both my large and small humidifier. My house has very hard water and I always fill my humidifiers with filtered water. There are three of these in a large humidifier and one in a small one. I put cartridges in humidifiers two months ago. During that time, I have not noticed any change or improvement in terms of the white "dust" generated by the large humidifier. A smaller humidifier leaves virtually no white residue. Both humidifiers are made by the same company and are similar except for the size. I don't know if the cartridge helps with less humidifier or produces less residue for other reasons. I suppose I could add more cartridges to a larger humidifier, but it's hard to clean as it's three plus an antibacterial stick. More than three seems excessive. Therefore, my test of these cartridges is inconclusive and of little help.