SeaKlear® Chitosan Clarifier™ 90215SKR 55 gal Drum. The original Chitosan Clarifier uses high-quality chitosan to deliver superior water clarity. It contains recycled shells from the seafood industry that would have otherwise ended up in landfills. This tried and true technology doesn't interfere with the performance of other pool products. It even works with high sanitizer levels and can be used at 1!.2!.. the same time as shocking your pool. Chitosan Clarifier works to improve filter performance while keeping pool water crystal clear.