Cal-Shock Calcium Hypochlorite | Fast Acting | 5 lb | 8 Per Case | First Choice

First Choice Cal-Shock quickly raises chlorine levels and clears cloudy water, helping you restore safe, inviting pool conditions with less guesswork. Packaged as a 5 lb pail (8 per case), it delivers a practical, reliable shock treatment that keeps pool maintenance straightforward for pros and DIY enthusiasts alike.

Use Cal-Shock after heavy swimming, following heavy rainfall, or whenever your pool needs a reset. It's designed to work quickly with standard pool sanitizers, delivering noticeable water clarity after disturbances. By restoring sanitizer effectiveness and clarifying the water, it reduces trial-and-error treatments and gets your pool ready for swimmers faster.

• Rapid chlorine boost to restore proper sanitization
• Converts cloudy water into clearer, more inviting swimming water
• 5 lb pail design, 8 per case for household or commercial use
• Simple application aligned with label directions for best results
• Ideal for frequent pool use, post-storm cleanup, or seasonal resets

Keep your pool in prime condition with First Choice Cal-Shock—add it to your cart and enjoy clearer water sooner.