I have problems with VERY hard water stains. In one bath I have a granite sink top and brushed nickel faucets. What can I use to clean the faucets that won't hurt the sink top. In the other bath I can't seem to get the stains off of a glass waterfall vessel sink. What can I use there. I already tried vinegar but it drips off the part that it needs to stay on. I even tried a razor blade which did take it off but it scratched the glass.