Review on 🌬️ BONECO AOS Hydro Cell A200 Humidifier Filter, 2 Pack - Activated Carbon, Gray, 2 Count by Damon Mertz

These hydraulic elements need no commentary to understand how to use them. They keep the inside of the AIR-O-SWISS water tank clean when the humidifier uses tap water. You can skip them IF your water is soft enough OR if you're using distilled water, but if you're counting on $1 a gallon it's a lot cheaper since you'll have to replace it about every three months on average. Please note that if you are expecting a difference between new and 3 months old, this will not happen. Time is the only criterion, so I switch every time I empty and rinse the tank.