Most of the scale is composed of calcium carbonate. Water Pal causes a chemical change that turns the scale to calcium bicarbonate, which is water soluble. Your body can absorb the calcium bicarbonate and use it. Some small pieces of the scale may accumulate in faucet screens and will need to be rinsed out. We recommend that you flush your water heater after 30 days since Water Pal will cause the scale on the heating elements to release; therefore, it may also increase the efficiency of the heater.