Cuprajake - no idea. All I can tell you is that I fill up my tank every week. It doesn’t smell, and the hoses are not slimy.
Then I wash the tank every 2 months with washing up liquid and sometimes a weak Milton solution.
The main purpose of using distilled water for cleaning (it’s fine to get it from the steam wand too!) is that it doesn’t leave streaky marks. I use the same methodology to clean the outside of the oven doors.
