Limescale

What is Limescale or Hard Water Scale?

Hard Water

"Hard water" is water which contains a high concentration of minerals such as calcium and magnesium ions. Hard water is formed when water percolates through deposits of limestone, chalk or gypsum which are largely made up of calcium and magnesium carbonates, bicarbonates and sulfates.

The dissolved minerals in the water precipitate causing the buildup of scale on surfaces, faucets, showers, pipes, water heaters, and appliances — anything that water flows through or touches. It causes numerous problems in laundry, kitchen, and bath.

Limescale

Scale or hard water scale is a hard chalky deposit consisting mainly of calcium carbonate (CaCO3) that often builds up inside kettles, hot water boilers, and pipework, especially that for hot water. It is also often found as a whitish deposit on the inner surfaces of old pipes, pots, and other surfaces where "hard water" has evaporated.

Hard water scale is caused by calcium and magnesium being left behind when hard water evaporates. Hard water, which is water that contains a higher mineral content, is the root cause of hard water scale. When it evaporates from a surface, it leaves behind calcium and magnesium deposits.

The formation of hard water scale is largely a consequence of the presence of soluble calcium bicarbonate in water. This compound can decompose when heated to form insoluble calcium carbonate, which makes up the large part of hard water scale.

Calcium bicarbonate dissolved in water can decompose when heated to form insoluble calcium carbonate — the main ingredient of hard water scale.

Hard water scale diminishes the luster of faucets, shower systems, and bathroom surfaces. It deteriorates and clogs aerators, cartridges, shower heads, faucets, shower systems, appliances, and pipes, thereby degrading their performance while significantly reducing their life span.

Used Cartridges with Limescale Buildup

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