Hey guys, I know that everyone here has opinions about everything, so I'm going to throw this one at you. Until this summer I always had well water at my house. Last year, though, an out of state mining company bought up an old mine under the hill behind my house and pulled the pillars to make a quick profit. Well the result was that the subsequent collapse ruined my well water. I had to hook up to the municipal water supply afterwards because my salt filter could no longer handle the iron and sulfur in the water. Now I have a strange thing going on. Instead of iron deposits in the commode, I now have a black ring that forms in the bowl every couple days, and around the rim water jets . It's not hard to remove, but comes back like clockwork. A sticky dingy film also forms in the shower. Again, not hard to remove, but persistent. As I have never had city water before, I don't know what this stuff is, or how to prevent it. Anybody got a clue?