For the great filtration results, We recommend using 2 PACK Humidifier Demineralization Cartridge per tanks and replacing it every 30 days It can strongly attch scale, rust, sulfides, suspended particles, and organic impurities in water, while effectively reducing odors to ensuring that the humidifier produces cleaner mists Applicable models: Suitable for 150, 200S, 160, 300, LV600S, 450S, 1000S Our Top Fill humidifier demineralization use ions exchange technology to effectively clean calcium and magnesium ions from water, reducing white scale and scale buildup, thereby improving the of humidifiers and extending their service life These Humidifier Demineralization Cartridges ensuring safe water and effectively saving you time and money