Where should sample water be collected during testing?

The most appropriate location for collecting water samples for testing is 18 inches below the surface and away from the return line. This depth ensures that you are obtaining a representative sample of the pool water that is not influenced by the immediate movement or mixing caused by the return jets, which can lead to inaccurate readings. Sampling from this depth helps to avoid surface contaminants such as debris, oils, and organic matter that may be present in the upper layer of water.

Collecting water from other locations, such as the pool corner, the edge of the pool, or directly from a fountain, may not yield accurate results. Sampling directly at the pool's edge might pick up debris or contamination that has settled near the surface, while obtaining water at a corner might not represent the overall quality of the pool water due to stagnant areas. Sampling from a fountain does not provide a valid sample of the pool water itself, as it interacts with a different water supply and system altogether. This comprehensive understanding reinforces why the specified method of sampling is essential for accurate water testing and pool maintenance.