Correct - and this is not only the case with Stadler (air humidifiers/cleaners), but also with Bonecos, for example - they also offer silver nitrite sticks (so that they are clean and germ-free and last longer).

It is indeed cheaper to change the water (and we clean the water tank and the water filter at regular intervals in the washing machine, Boneco also states that this is how it works).

Is this not possible and if you don't want to shell out the money for such a "silver cube": In the outdoor accessories market there are water disinfection and preservation liquids for little money, 1 single drop of which should be more than enough (so that such a cheap bottle then lasts an extremely long time)).

Sorry for texting you... Conclusion: No, you don't really need it, if you do: there are alternatives.

LG, have a nice weekend