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GLB® SuperSonic Pool Shock | 73% Cal Hypo

GLB®  |  SKU: 71442A-1

Chemical Type: Chlorine Shock (Cal Hypo)

$7.50 $22.00
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2 In Stock


GLB SuperSonic is a highly effective multi-purpose product that sanitizes, clarifies, prevents algae and shock treats your pool. It is convenient, easy to use and won't over stabilize your pool water. The fast-acting formula can be used on all pool surfaces, does not contain cyanuric acid and leaves no residue.

SuperSonic sanitizes, clarifies, fights algae and won’t overstabilize pool water. It’s safe for use on all pool surfaces and leaves no residue.


  • Contains 73% available chlorine.
  • Add 1 lb. per 10,000 gallons directly to the pool.
  • For best results, add during the evening hours.
  • Compatible with chlorine and salt water chlorine sanitizing systems.

Directions & Dosage - 73% Cal Hypo Granular Pool Shock

Instructions for Pool Opening:

  1. Adjusting pH Levels: Ensure the pH level of your pool water is between 7.2 and 7.6. Use a reliable pH meter to check and adjust as necessary.
  2. Shock Treatment Procedure: Follow the guidelines for a "Shock Treatment" provided below.
  3. Dispersion and Testing: After adding the shock treatment product, wait for 30 minutes to allow the product to fully disperse throughout the pool water. Then, use a pool test kit to measure the free available chlorine levels. Repeat the shock treatment if the chlorine level is not within the desired range.

Guidelines for Shock Treatment:

  • Routine Maintenance: Perform a shock treatment weekly, or more often if needed, to prevent issues with your pool. This involves adding between 9 to 18 ounces of the product for every 10,000 gallons of pool water, aiming for a chlorine level of 5 to 10 ppm (parts per million).
  • Addressing Pool Problems: If your pool shows signs of algae, experiences high usage, or after events like heavy rain or storms, additional shock treatments might be necessary. These treatments help in managing algae growth, unpleasant smells, and eye irritation. Always verify the chlorine levels post-treatment using an appropriate test kit.

Managing Algae Growth:

  1. Initial Steps: Start by applying a "Shock Treatment" as detailed above. Focus on adding the product near the algae concentrations on the pool's sides or bottom.
  2. Repeat Treatments: If the algae persist, it may be necessary to repeat the shock treatment.
  3. Post-Treatment Care: To avoid stains or bleaching effects after treatment, promptly brush the algae off the pool surfaces, vacuum the pool, and cycle the water through the filter.
  4. Preventive Measures: To keep algae at bay, regularly use an algaecide of your choice, adhering to the instructions on the algaecide product label.

Shipping Details

All orders placed before 3PM on Monday - Saturday will be shipped same-day
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Inventory available in Denver, CO | Jacksonville, FL | West Berlin, NJ

Ingredients & MSDS - GLB Supersonic 73%

Calcium Hypochlorite:73% | Other Ingredients:27% | Available Chlorine:70%

There is currently no MSDS on-file for this product.

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