When should you perform a shock treatment?

Performing a shock treatment after heavy usage or following significant rain is crucial because both scenarios can lead to elevated levels of contaminants in pool water. After a busy day at the pool, the introduction of oils, bodily fluids, and other debris increases the demand for chlorine, making it less effective at sanitizing the water. Similarly, rain can introduce organic matter, debris, and even dilute the sanitizer levels in the pool, leading to potential biological growth.

Conducting a shock treatment in these situations re-establishes proper sanitation levels by breaking down chloramines (which cause unpleasant odors and irritation) and effectively killing any potential bacteria or algae that may have been introduced. This timely intervention ensures a safe swimming environment and maintains overall water quality.

Other options do not emphasize the appropriate timing for shock treatment based on actual conditions that affect water quality. Regular weekly shock treatments, or those only done in winter or pre-season, do not address immediate and pressing issues caused by user load or environmental factors.