
By Karen Rigsby and Zach Hansen
Pool owners respond more intently to cloudy water than any other water-related issue due to its direct esthetic effect on the pool’s appearance. It can easily be identified by visual observation; any pool owner can recognize cloudy water and know it is an indication something requires attention. Where the difficulty lies for pool professionals, however, is diagnosing the specific problem and devising a solution that will adequately clear the water.

Water cloudiness or turbidity is caused by the introduction of suspended particles that are invisible to the naked eye. A similar analogy would be the particles in the air that cause smoke. These impurities are introduced to the water via a myriad of sources. Essentially, any particulate debris that comes from the surrounding environment, (e.g. pollen, dirt, clay and silt, inorganic/organic matter, algae or microbial organisms) can contribute to cloudy water. Even bathers and source water can contribute to the problem. Consequently, swimming pools are constantly exposed to such contaminants and require proper maintenance to ensure a clean and safe swimming environment.
Pool management systems prevent cloudy water through two distinct mechanisms—chemically (proper water balance) and physically (filtration). This article will discuss the causes of cloudy water as a direct result of system breakdown.
Chemical causes of cloudy water
Improper water balance is directly attributable to cloudy water. Water balance describes water parameters to ensure optimal conditions for the pool and is dictated by the calcium carbonate (CaCO3) equilibrium equation below:
Change in pH
Change in temperature
CaC03 + H2O + CO2 <——————-> Ca+2 + 2HcO3–
Calcium Carbonate (scale) + Water + Carbon Dioxide + Calcium + Bicarbonate
The equation shows that pH, carbonate/calcium (Ca) concentration and water temperature each have an impact on the formation of calcium carbonate scale. The following sections discuss each parameter and their respective impact on cloudy water.
The equation shows that pH, carbonate/calcium (Ca) concentration and water temperature each have an impact on the formation of calcium carbonate scale. The following sections discuss each parameter and their respective impact on cloudy water.