I have used RO water. It works very well. I used distilled last week for two barrels and it worked very well too. I have used tap water and that has worked okay - but, I think the minerals in the water occasionally would dry to the barrel before I could wipe it down with alcohol. The water spotting would incorporate into the next rust cycle no matter what. So, whatever I use, it will be mineral free to the degree I can make that possible. I don't think filters can do that. So it is either RO or distilled for me.

Brent

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BrentD, (Professor - just for Stan)
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