How do you remove scale buildup?

Scale is defined as hard deposits, consisting primarily of calcium carbonate, that form on pool surfaces and equipment due to high total hardness or other out of balance water conditions. Total hardness is a measure of the amount of calcium and magnesium in the water. These minerals occur naturally in varying amounts in fill water. The calcium hardness range for vinyl, painted or fiberglass pools is 175 - 225ppm.  The ideal range for plaster pools is 200 - 275ppm.

High total hardness can result in scale formation. If the hardness is too high, the water is considered saturated meaning the water cannot hold the calcium and magnesium in solution any longer, and the minerals begin to fall out of solution, or crystallize. This causes the water to become cloudy, and eventually scale deposits can form on the pool surface and equipment. The deposits are very hard, usually rough and sandy, and are white to light tan in color. More severe deposits can actually look like concrete with sharp edges.

Unfortunately, it is not easy to remove these deposits. If scale has been present for some time on the pool surface, it is not easily removed.  If the buildup has accumulated on equipment, those affected parts sometimes have to be replaced.

To remove the scale, backwash the filter and add 1 quart of Simplicity Scale and Stain Control per 10,000 gallons directly to the pool, then lower the pH to 7.2 and brush the affected areas for one week. When deposits are gone, chemically clean the filter with Simplicity Filter & Cartridge Cleaner to remove scale from the filter.  If the deposits do not loosen, it will probably be necessary to drain and acid wash the surface to remove them. If the pool surface is vinyl, the liner will have to be replaced.

The only way to lower the hardness level in a pool is to drain part of the water and refill with fresh water with a lower total hardness. If this is not feasible, Simplicity Scale and Stain Control can be used to help hold calcium in solution, preventing scale buildup. Add 16 ounces per 10,000 gallons monthly for maintenance.