White or tan particles in the water usually come from internal plumbing. This material is pipe scale and is a combination of calcium carbonate and magnesium carbonate. Calcium and magnesium carbonates are naturally occurring minerals and are not a health hazard. Over time, these minerals can deposit on the inside of your pipes and then begin to flake off. Although this process usually occurs slowly over a long period of time, there are three common circumstances that can cause it to happen rapidly:

• If your water was turned off for repair work, the pressure and turbulence created when it is turned back on can dislodge the minerals from the pipes
• If you install a water softener, the softer water can begin to re-dissolve the minerals from the pipes and pieces may begin to break loose
• If you have galvanized iron pipes, they will corrode over time and gradually swell up on the inside, causing the minerals to flake off (Although pipe scale is not a health hazard, it can clog washing machine screens, shower heads, and faucet aerators. There is no practical way to remove pipe scale from the inside of your pipes; if the problem is severe, you may want to consider re-plumbing.)

The water heater is another source for white or tan particles. As the water is heated, calcium and magnesium carbonates precipitate out of the water, forming white or tan sand-like deposits. As you use the hot water, these minerals can be carried along clogging washing machine screens, shower heads, and faucet aerators. To keep mineral deposits from accumulating in the water heater, flush your water heater at least once a year. Flushing regularly also extends the life of the heater and makes it operate more fuel efficiently. Instructions for flushing can be found in the Water Quality FAQ on hardness.

If you are experiencing floating white particles, the water heater is the likely culprit. A water heater contains a plastic dip tube, which is an extension to the inlet of the water supply. The tube directs the cold incoming water to the bottom of the tank. As the tube gets old, it can disintegrate, sending white particles into the hot water. These particles are brittle and vary in size from small irregular pebbles to longer shards. Contact the manufacturer or vendor for advice on how best to repair the water heater.