I have black water coming out of the faucet for my bathroom whirlpool tub. It's very black when the water is first turned on with some black sediment. I have well water and the last water test didn't come up with any answers. I don't believe it is the water heater as the water is perfectly clear, even slight tint of blue when the water is coming out of the kitchen faucet. The water goes through a water softener. At one time the line to that bathroom had a circulator running. I have since turned it off thinking it might be the reason for the black then gray water. I also turned the temperature down a bit. As the bathroom shower and sink don't have a problem it seem to be that the copper line for the whirlpool, because it doesn't get used as much, is the issue. I'd like to know if the pipes can be cleaned or will they need to be replaced as I have run a lot of water through it trying to figure out what to do. I would be nice to know what caused it so that it can be prevented in the future. Any thoughts would be most appreciated.