The AquaPill WinterPill AP71 makes winterizing and opening your pool a breeze. The AP71 features four different chemicals – clarifier, scale inhibitor, stain inhibitor and enzyme enhancer - to preserve your pool’s chemistry and keep it maintenance free all winter long. Compatible with all filters and types of pools, the AP71 is easy to use and can handle up to 30,000 gallons of water with ease. AquaPill recommends replacing the AP71 every six months.