Minerals such as silver and copper have long been known for their sanitizing antimicrobial properties. Nature2 cartridges, bring that natural sanitization to your swimming pool. Nature2 is proven to allow you to reduce chlorine use up to 50% and is guaranteed to kill bacteria and control algae. Whether you use chlorine or salt water, Nature2 works to optimize your system and reduce the use and effects of traditional harsh chemicals. That means less red eyes, itchy skin, and unpleasant odor. Enjoy pool water, naturally.