I've used distilled water from the beginning. I do clean with vinagar as required but other than that I rinse it out with my RO system and let it air dry. I clean all connectors. I've used the same tank for a full year without any issues.

I've been using the machine for over a year now. What I can tell you is that in my area the water tand could be better at first (In winter) my tank would be dry in the morning so I added a humidifier in my room and that helped. Any sleep over 7 hours and th tank will generally be dry. I did play wit...