After-shock and algaecide clean-up… and much, much more! All chemical treatments, including shocks, algaecides, sanitizers and oxidizers, leave behind residue every time they are used. Swimmers and pets also leave behind suntan lotions, oils, dander, hair, etc. And, of course, you can't stop the pollen and dirt from getting into your pool. These constant problems create risky and unsanitary conditions that demand a simple, long-term solution. PoolGel™ uses revolutionary gel-delivery technology to continuously release a proprietary blend of concentrated active ingredients that bind and remove all these contaminants and residues 24 hours a day. Simply drop the new PoolGel into your skimmer basket — no mixing, no measuring. It's that easy! Replace once dissolved. Each PoolGel lasts for weeks.