I did a small section with some Klenztone #1 diluted 1-2 and had to re apply at certain areas several times because of copper stains. Now a week later it is rusting the stone in all the areas where the copper was. Very strange. Klenztone usually removes rust but it seems to be causing it this time. There is another area this has happened as well where it is super dark on the edge of a step in a couple small places. This was sealed with Dry Treat the last time it was done.
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