I put a razor in one with regular tap water instead of distilled and it made it rusty. Superficial, it did wipe off with some paste.
Yes! Now I remember...yes, it was the tap water that did it rather than using distilled...now you've got me wondering...maybe 15-60 minutes with some evapo-rust might really get into the pits...could keep an eye on it...good to hear it just wiped off.