Review on 🌬️ Vornado MD1-0002 Replacement Humidifier Wick Filters, 2-pk: Enhance Air Quality with High-Performance Filters by Susan Rolfs

. Some reviews seem to misunderstand how it works. They aren't really filters. They are wicks. Water is absorbed by the cellulose fibers. The fan draws air in through them and exits at the top, forcing out humidified air. Easy. Maximizing the wet surface area of the wicks is key to humidifier efficiency. Tap water contains trace or even more minerals. They crystallize in the fibers and over time the effectiveness of the wicks decreases significantly. In some places they appear dry and hard. The time required for this depends on the water hardness and the humidity of the environment. They dry faster when the machine is on "low". The wick needs to be changed more frequently when it gets very dry, usually in the middle of winter. Some people have tried to "clean" them - I've tried - but it just doesn't work. If the wick is sufficiently mineralized, the humidifier simply cannot do its job. Soaking them in warm water can easily revive them for a few days, but it won't last long and eventually they will start to fall apart. I've found that you can extend their lifespan by turning them over every time you fill the jars with water. Thanks to this, I used the kit for about two months at the beginning of the season. Replace as needed. There is no way around it if you want to humidify the room. As with inkjet printers, the Vornado Evap40 (the best I've tried) is relatively inexpensive. And like ink cartridges, the company makes $$$ from selling wicks. That's the problem. These wicks appear to be saturated with salt, which slows the growth of bacteria. Over time, the salt will wash out, another reason to change the wicks regularly. As spring approaches, the microbes begin to grow freely again. Then you may come across red algae. Drain unit, wipe with disinfectant, dry and restart with new filters. Pretty soon, you'll be able to put away your humidifier until late fall next year. Buy a replacement manufacturer. Fakes will never save you much and will never work.