HXEternal 1 kg Multifunctional Chlorine Tablets are suitable for swimming pools, hot tubs, and spas. These 4-in-1 dispenser tablets contain stabilised chlorine, a clarifier, and an algaecide to keep your water sparkling clear and free from bacteria. The stabiliser minimises chlorine loss from sunlight, the clarifier prevents cloudy water, and the algaecide prevents algae growth, keeping your pool or hot tub from turning green. These slow-release tablets last approximately 3-4 days depending on water flow and can be used in floating dispensers, chemical feeders, and skimmer baskets. For optimal results, maintain a free chlorine range of 3-5 mg/l (ppm) for hot tubs and 1-3 mg/l (ppm) for swimming pools. Always maintain pH levels between 7.2-7.6 for best performance. For freshly filled hot tubs, an initial shock dose of 50mg/l for 1 hour or 20mg/l for 2 hours is recommended. These tablets have a minimal effect on water pH.