Jason Watkins
New member
Customer had a drain from an AC unit coming out on the ceiling of his front porch (??), and it rusted the slate tiles up. I tried using half water, half F9 and it didnt seem to do much. Used straight F9, sprayed a couple of coats on a tile, and still didnt see much change. Is there a trick to getting the rust off of these slate tiles? (BTW, I'm assuming it's rust.)