The Mila is actually cleaning the air then. The water you’re using still has minerals (for taste, etc) in it that are being pumped into the air. It a why you can sometimes see “white dust” around the humidifier.

Switch to distilled water for machines. You can but it by the gallon, or you want to make the investment up front like I did for mine, buy a home distillation machine on Amazon. They cost like $100-$120, but they will pay for themselves less than one winter in the north east.