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Highlights
- All-in-one solution to increase chlorine levels, prevent bacteria, algae, stain, and scale
- Reduces skin and eye irritation, improves filtration, and softens pool water
- All-in-1 weekly Cal Hypo pool shock restores crystal clarity within 24 hours
- Cal Hypo based formula sanitizes without adding cyanuric acid (CYA) to prevent overstabilization
- Compatible with all pool types including vinyl-lined pools and saltwater systems
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About this item
Product details
HTH™ Shock Ultra: The All-In-One Pool Care Solution
HTH™ Shock Ultra is an all-in-one weekly formula that takes care of all your pool maintenance needs. It increases chlorine levels, kills and prevents bacteria and algae, reduces eye and skin irritation, prevents stains from metals, prevents scale, improves filtration, and softens water. The best part? You'll see results in just 24 hours!
No More Cyanuric Acid Worries
Unlike traditional chlorine products that contain cyanuric acid (CYA), HTH™ Shock Ultra is different. Excessive CYA can lead to overstabilization or chlorine lock, which clouds your water and promotes algae growth. HTH™ Shock Ultra's fast-acting, fast-dissolving Cal Hypo based formula provides chlorination without adding extra CYA, ensuring a beautiful sparkle all season.
Safe for All Pool Surfaces
HTH™ Shock Ultra is ideal for all pool surfaces and won't fade your liner. It's the perfect solution for maintaining the beauty and cleanliness of your pool without causing any damage.
Easy to Use
Using HTH® Shock Ultra is simple. Just follow the on-pack instructions according to your pool size and add HTH® Shock Ultra directly to your swimming pool water or skimmer. The built-in Visible Blue Action lets you know it's working! For best results, apply HTH® Shock Ultra as part of your weekly pool care routine to keep free available chlorine levels between 1 and 4ppm.
info:
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Specifications
Product Type: All-in-1 Weekly Cal Hypo Pool Shock
Usage: Weekly
Effectiveness: Solves 90% of pool problems within 24 hours
Clarity Restoration: Restores crystal clarity in 24 hours
Suitability: Suitable for all pool types
Member ratings & reviews
Filtered and sorted results would be available on the new 'Customer ratings & reviews' page.
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Showing 1-2 of 2 reviews
Jun 13, 2026
Reviewer name: anonymous
5 out of 5 stars
Works really well
great price would definitely buy again
Helpful?1FWTBNUKRWFQ15059505000
Apr 25, 2026
Reviewer name: anonymous
1 out of 5 stars
Junk
This stuff is awful. Doesn’t dissolve well. Like it has waterproofed grit in it
Helpful?1FWTBNUKRWFQ15059505000
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