Calcium scale is an issue for many pool owners, especially in areas of the country that have hard water. It is often also called limescale, and it is the result of calcium carbonate that deposits on the walls at the water line or in crystals or thin sheets on the water surface.
What Causes It?
Calcium scale results from the water in your pool evaporating so that the calcium crystallizes on the surfaces or the surface of the water. This scale by itself is white, and you will often see it build up on the metal surfaces of the ladder or in the corners of the pool surround. It can also mix with dirt and algae to become darker and more noticeable. The calcium can also form together into sheets covering the entire surface of the pool. Calcium scale is the result of a combination of factors: high calcium hardness that provides the excess calcium (over 400 ppm) and high alkalinity (high pH) and high temperatures that trigger the process.
How To Remove It
Since the root of the problem is excessive calcium, you may be assuming that you have to drain your pool to solve it, but that is not always the case. Most calcium scale can be removed with muriatic acid, an acid cleanser, or even pH Decreaser. Don’t use CLR, since that is intended for household use and will add chemicals you shouldn’t have to your pool. You will have to lower the water level enough to get to the area that needs to be cleaned, and once you do, the process is pretty simple. Knock through any big chunks on your tiles with a putty knife and then apply the acid with a sponge or pour it over with a watering can. You can also use wet-dry sandpaper or pumice on the tile to lightly sand away the scale. For scale on the plaster, you might consider draining the pool and pressure or acid washing to clean the whole surface. Or you could sand off all the rough bits in the entire pool with a PoolStone. The truth is, however, that if your pool is white, you probably won’t even notice the scale build up on the plaster.
How To Prevent It
Once the scale is gone, or before it even happens, prevention is key, and that comes with proper pool maintenance. Avoid shock that adds extra calcium to the pool and uses sequestering agents to keep the calcium that is there locked in solution. Lower your pH so that there is less opportunity for the calcium to precipitate out, and brush and vacuum often to remove it as it builds up. Finally, a clarifier can draw the calcium particles together into a clump that your filter can then remove
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We here at Sunrise Premiere Pool Builders LLC can build and install your pool or spa and also provide you with pool chemicals, services, and more. If you have any questions, give us a call at 410-349-3852 today. To keep up with our latest projects and for helpful tips and tricks, be sure to follow us on Facebook, Twitter, Google+, Pinterest, and LinkedIn.