If you've notice black particles in your water, they are from the hot water heater. They are often most noticeable sticking to the sides of the bath tub or in a kitchen sink - anywhere hot water can sit for several minutes.

Black particles are caused by deterioration of the rubber lining in the flexible hose connected to hot water heaters. The hose has a flexible, metal outer casing, but is lined with black rubber. A mixture of the heat from your hot water tank and the chlorine in the water deteriorates the lining, leaving particles that adhere to fixtures.

To correct this problem, replace the flexible hose. A copper hose can be purchased at any plumbing supply store. Be sure to clean and flush all aerators after the hose has been replaced.