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HTH Extra Super Chlorine Shock (454 g)

HTH Extra Super Chlorine Shock (454 g)

SKU: 30318

$8.99 $10.99 You save 18%
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Detailed Product Description

HTH Extra Super Shock is fast acting and powerful! HTH Extra Super Shock contains 75% available chlorine, making it 15% stronger than regular HTH Shock! Its fast dissolving, extra fine formula is made with a patented process that makes it perfect for weekly shock treatments and killing algae. No need for messy liquid chlorine for sanitizing your pool, HTH EXTRA is easier to store and use. 1 pouch is approximately equivalent to 10 liters of liquid chlorine.


  • Compatible with chlorine, ozone, mineral systems and salt water pools
  • Calcium Hypochlorite
  • Contains 75% available chlorine
  • Fast dissolving, extra fine formula - no need to pre-dissolve
  • Perfect for weekly shock treatments
  • Kills algae

Directions for use:

Always adjust pH between 7.2 and 7.4 prior to using this product. Maintain recommended daily levels as determined by testing kit: free available chlorine 1.0 - 3.0 ppm, pH 7.2-7.8, total alkalinity 80-120 ppm, calcium hardness 200-300 ppm

Superchlorination of stabilized pools: For pools stabilized with cyanic acid, periodic superchlorination is necessary to provide sufficient free available chlorine to control algae, destroy unfiltered organic contaminants, minimize odours and keep water sparkling clear. Superchlorinate by broadcasting over a large area of the pool surface, mainly in the deep end at the rate of 65 g/ 10,000 L. Superchlorinate every 14 days when the temperature of the water is below 27°C. Treatment every 7 days is recommended when the temperature is higher, bathing loads are heavy, pool water appears dull or lazy, unpleasant chlorine-like smell is present, excessive eye irritation occurs, or after heavy rains. Pool should not be entered until the chlorine residual is 1.0 - 3.0 ppm.

Shock Treatment For Control Algae: If algae develops, resulting in a green colour and slimy feeling, shock treatment is necessary. Broadcast over a large area of the pool, mainly at the deep end, at a rate of 130 g/ 10,000 L. If the pool sides or bottom develop algar spots, direct as close to the algae as possible. NOTE: Prolonged contact with the pool surface may cause staining or bleaching. Immediately after treatment, thoroughly clean the pool by scrubbing surface of algae growth, vacuuming and cycling through the filter. If necessary, repeat the treatment. Pool should not be entered until the chlorine residual is 1.0 - 3.0 ppm.

Start-up: For initial chlorination of pool water add 65 g/ 10,000 L. Allow five minutes for dispersion and then test the chlorine residual with pool test kit. If below 1.0 ppm repeat this dosage until 1.0 ppm is obtained. Pool should not be entered until the chlorine residual is 1.0 - 3.0 ppm.

Winterizing: While the water is still clear and clean, prepare for long periods of disuse by gradually applying 390g/ 10,000 L. Run the filter until dispersion is complete. Cover the pool with a plastic pool cover and prepare the heater, pump and filter components for winter by following the manufacturer’s directions. When the pool cover is removed in the spring, follow the Start-up directions.

Storage and Disposal: Keep product dry in tightly closed container when not in use. Store in cool, dry well-ventilated area away from open heat or flame. Do not reuse empty container. Rinse empty container thoroughly with water to dissolve all material before discarding. For information on the disposal of unused, unwanted product, contact the manufacturer or provincial regulatory agency. Contact the manufacturer and the provincial regulatory agency in case of a spill and for clean-up of spills.

Warranty Coverage: HTH Chemicals come with a 30 Day Limited Manufacturers Warranty.

Start a Warranty Claim:To begin a claim please email with a photo showing the defect(s)/issue with your HTH Chemical and include a brief explanation of what occurred.

Customer Reviews

Review by Joe/Jessica Y on June 9, 2023

Verified Review

Great product

Review by Diane L on August 9, 2022

Verified Review

Review by Khadej F on August 2, 2022

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Very goo product

Review by Robert F on October 5, 2021

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Review by Marielle M on September 20, 2021

Verified Review

Worked amazingly well!

Review by Gursev B on May 21, 2021

Verified Review

A great product that delivered on everything it claimed. Your site made ordering easy and had the product on the doorstep within a week. I am a happy customer !!

Review by Maura M on July 5, 2020

Worked amazingly well! I'm on here now to buy more!!!

Review by Kari E on June 8, 2020

Verified Review


Review by Jason H on June 4, 2020

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Review by Jason H on June 4, 2020

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Great product at a great price!

Review by Darrin M on August 29, 2019

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HTH Extra Super Chlorine Shock (454 g) $8.99

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Page ID: 6583 Page Type: products