I use purified water with my Brita filter humidifier and I have very very few limescale deposits! Operating a humidifier with distilled water simply makes no sense! In winter, the humidifiers need 2 - 4 litres of water daily, depending on the size of the flat. Think about how much distilled water you have to buy! The additional costs for this would be far too expensive and you can also dispose of a lot of plastic bottles. The Xiaomi Rainforest looks quite stylish, but this device is not well thought out. Why doesn't the Xiaomi company install a limescale filter? That would have made sense. The plexiglass on the device will look scratched and calcified over time, and of course you can only use a soft cloth to clean it (glass would have been much better, but also more expensive!) The water feature is a funny gadget. The joy of it will probably be rather short! A humidifier has to perform well and be easy to clean.....naja this device is probably intended more for presentation....lol......! I recommend that you run the unit with Brita water in any case to reduce limescale and also save costs!

Greetings
Daniel