I use the filters for 4 months to keep the device affordable for the weakest. I use lactic acid for espresso machines 1 to 3 units of water in a sink. I put the filter in it, the lime melts. Use warm water, not too hot. Add 1 tablet of hygiene tab. Can also be ordered from Stadler Netherlands. The filters do not break. They work odourlessly and last twice as long. Good luck. Stadler will not be happy, but must admit that the company supports durability and miljeu. Without this measure, I would have to switch to filterless air washers. Greetings from a lime😆uluent Dutchwoman.

The filter mats do not always soak up the water all the way to the top, so over time they turn yellow and smell musty. I then started to turn the filters regularly so that they are always well soaked, which solved the problem to some extent.

I have just put my 3 Oskars into summer sleep. Cleaning is quite simple: throw away the filter - order new ones, write off the grille in 2 places at the Big - otherwise in one (from the inside) and clean the grille under running water. Clean the "propellers" from dust and basically remove dust. Clean the tub (if necessary with descaler - but not too sharp, so that the surface is not damaged). Put back in the box with new filters and ready for the next winter!

The filters should not be cleaned but replaced. Depending on use and air quality, they should be replaced between 1-3 months. I change them every month.