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HTH 32-oz Cal Hypo Pool Shock

Stay all clear for cannonballs! This fast-dissolving, convenient 4-in-1 formula kills bacteria and algae, reduces chlorine odor and irritation and quickly restores crystal clarity
Visibly brilliant sparkle: This Cal Hypo based formula sanitizes without adding cyanuric acid (CYA) to prevent overstabilization or chlorine lock
Compatible with all swimming pools: This product is great for all pool types including vinyl-lined pools and salt water systems

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HTH® was developed with the pool owner in mind. We know that maintaining your pool water can be a lot of work. That’s why we're here every step of the way, helping you clear the uncertainty from pool care. With economical, easy-to-use solutions, HTH® is designed to work hard so you're prepared to tackle whatever life throws in your pool. From balancing your water to treating green water, we offer a full line of products to keep your pool water healthy and your swimmers happy.

Stay all clear for cannonballs! This fast-dissolving, convenient 4-in-1 formula kills bacteria and algae, reduces chlorine odor and irritation and quickly restores crystal clarity
Visibly brilliant sparkle: This Cal Hypo based formula sanitizes without adding cyanuric acid (CYA) to prevent overstabilization or chlorine lock
Compatible with all swimming pools: This product is great for all pool types including vinyl-lined pools and salt water systems
You're all clear with HTH: For best results, use with HTH® 6-Way Test Strips to test and balance your swimming pool water twice weekly
Follow the on-pack instructions according to your pool size to add HTH® Shock Advanced directly to swimming pool water or skimmer; For best results, apply HTH® Shock Advanced as part of your weekly pool care routine to keep free available chlorine levels between 1 and 4 ppm
This product is great for all pool types and won't fade your pool liner