Saltwater pools have gained popularity as an alternative to traditional chlorinated swimming environments. While often perceived as “chlorine-free,” these pools operate on a system that still relies on chlorine for sanitization. A saltwater pool generates chlorine on-site from dissolved salt. This inherent production system maintains water purity, but specific circumstances can necessitate supplementing the pool’s sanitization.
The Role of Chlorine in Salt Water Pools
A saltwater pool system uses a salt chlorine generator to produce chlorine. This generator converts dissolved sodium chloride, or common pool salt, into hypochlorous acid through electrolysis. Hypochlorous acid is the primary sanitizing agent, neutralizing bacteria, viruses, and algae to keep the pool water clean and safe.
The generator continuously produces a steady supply of chlorine, which disinfects the water before reverting back into salt. This cycle allows the salt to be reused repeatedly. Despite producing its own chlorine, a saltwater pool is fundamentally a chlorine-based system, meaning chlorine chemistry principles still apply to its ongoing maintenance.
Reasons to Supplement Chlorine
Adding supplemental chlorine to a saltwater pool becomes necessary in specific situations to maintain water quality. One common reason is for shock treatment, which involves adding a high dose of chlorine to rapidly oxidize contaminants. This is useful after heavy bather loads, significant rainfall, or if the pool shows signs of algae growth. The existing chlorine production might not be sufficient to handle these sudden increases in demand.
Another scenario involves issues with the salt chlorine generator itself. If the salt cell malfunctions, needs cleaning, or reaches the end of its lifespan, its chlorine production capacity will diminish or cease. In such cases, manually adding chlorine ensures the pool remains sanitized while the generator is repaired or replaced.
An algae outbreak also requires an immediate, potent boost of chlorine beyond what the generator can produce. Similarly, when opening or closing a pool for the season, an initial chlorine boost provides a strong sanitizing treatment. Rapid chlorine demand can also occur during extremely hot weather, which accelerates chlorine degradation, or during large pool parties where increased organic load quickly depletes existing chlorine levels.
How to Safely Add Chlorine
When adding supplemental chlorine, selecting the correct type and following precise application methods are important for safety and effectiveness. Liquid chlorine, which is sodium hypochlorite, is a suitable choice as it adds only chlorine and sodium, without introducing other chemicals like cyanuric acid. Granular shock, such as calcium hypochlorite or dichlor, can also be used, but be aware that dichlor adds cyanuric acid, which can accumulate over time and reduce chlorine effectiveness if levels become too high. Before adding any chemicals, always test the pool water to determine current chlorine levels, pH, and alkalinity.
To calculate the appropriate dosage, consult the product instructions based on your pool’s volume and the desired chlorine level. For liquid chlorine, slowly pour it into the pool’s deep end, away from skimmers or returns. Granular products should first be dissolved in a bucket of water before being slowly poured into the pool. Always wear appropriate safety gear, including gloves and eye protection, and ensure adequate ventilation. After adding the chlorine, run the pool pump for several hours to ensure the chemical is thoroughly circulated and distributed throughout the water.
Maintaining Pool Health After Adding Chlorine
After adding supplemental chlorine, it is important to monitor the pool’s chemistry to ensure balance and continued health. Re-test the water after a few hours, or the following day, to confirm that chlorine levels have reached the desired range and that other parameters like pH and alkalinity remain balanced. If necessary, adjust other chemicals to bring the pool back into its optimal operating range. This step is important because significant changes in chlorine can sometimes affect other chemical levels.
Monitor the salt chlorine generator’s output to ensure it resumes normal operation once the immediate need for supplemental chlorine has passed. Adjust its settings as needed to maintain a consistent chlorine residual. Implementing consistent pool maintenance practices, such as regular brushing, skimming, and filter cleaning, can help minimize the frequency of needing supplemental chlorine. These preventative measures reduce the overall organic load, allowing the salt chlorine generator to more easily maintain proper sanitation levels.