How is the Total Dissolved Solids (TDS) level in a pool affected?

The Total Dissolved Solids (TDS) level in a pool is primarily influenced by the accumulation of various chemicals, minerals, and contaminants present in the water. As pool water is used and various substances are introduced—such as disinfectants, algaecides, oils, dirt from bathers, and organic material—TDS levels increase. Over time, even through the addition of water to replace evaporation, there is a gradual buildup of these materials, which contributes to higher TDS readings.

While other factors like sunlight, temperature, and pool usage do have specific effects on water chemistry and clarity, they do not directly increase the TDS level in the same way that the accumulation of substances does. For instance, sunlight can lead to the breakdown of certain chemicals, and temperature can affect the water's ability to hold dissolved substances, but neither contributes to the actual quantity of dissolved solids. Frequent pool usage can introduce contaminants that might contribute to TDS, but it’s not the core reason for its overall increase. Hence, the understanding that TDS is largely a product of accumulated materials in the water is key to maintaining pool health and ensuring balanced water chemistry.