I tried searching for some plumbing forums, but didn't find much. So, I thought I'd ask the members here a question. In on of our bathrooms there seems to be brown water coming out of the tap and also into the toilet. It only happens with the cold water on. It sounds like some sort of pipe problem to me, but I really don't want to call a plumber ($450 bill last time for an hour of work!). Any ideas would be greatly appreciated!