Calcium Buildup in Desert Pools

If you look closely at the waterline of almost any pool in Southern Nevada, you will likely see a white, crusty ring. This is calcium scaling, and it is one of the most persistent challenges of maintaining a pool in a desert environment.

The Source of the Problem

The municipal water supply in Las Vegas and Henderson is notoriously "hard," meaning it contains high levels of dissolved calcium and magnesium straight out of the tap. When you fill your pool, you are introducing these minerals into the system.

The Evaporation Multiplier

During the summer, a typical residential pool can lose up to a quarter-inch of water per day to evaporation. When water evaporates, it leaves the heavy minerals behind. As you use an auto-fill valve or hose to replace the evaporated water, you are adding even more calcium to the pool. Over time, the concentration of calcium hardness skyrockets.

Damage to Plaster and Equipment

When calcium levels become too high, the water becomes oversaturated and can no longer hold the minerals in solution. The calcium precipitates out, forming scale on your pool tiles, plaster, and inside your plumbing. More critically, it builds up inside your pool heater's heat exchanger and salt chlorinator cells, drastically reducing their efficiency and lifespan.

Management Strategies

Managing calcium requires strict pH control, as high pH accelerates scaling. We also utilize specialized sequestering agents that bind to calcium molecules, keeping them in solution. However, once calcium levels exceed 800-1000 ppm, the only true solution is a partial or full water drain to reset the mineral baseline.