Leslie's - 1 lb Power Powder Plus Calcium Hypochlorite Pool Shock

Item No. 18748 | Manufacturer SKU: W8000346
Item No. 18748 | Manufacturer SKU: W8000346
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
Leslie's  1 lb Power Powder Plus Calcium Hypochlorite Pool Shock
$9.99
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Leslie's Power Powder Plus 1 lb is our strongest pool shock with 73% Calcium Hypochlorite killing bacteria, algae, and contaminants for clear, sanitized pool water. Product packaging may vary, with no change to product composition or weight. More Details
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Leslie's Power Powder Plus 1 lb is our strongest pool shock with 73% Calcium Hypochlorite killing bacteria, algae, and contaminants for clear, sanitized pool water. Product packaging may vary, with no change to product composition or weight.
  • Kills bacteria, controls algae, and destroys organic contaminants
  • Concentrated chlorinating granular Cal-Hypo pool shock
  • Fast dissolving
  • Low Residue
  • 73% Calcium Hypochlorite
  • 70% Minimum Available Chlorine
  • Fast acting solution for swimming pool problems
  • Great for super chlorination and routine maintenance use
  • Non-Stabilized - No Cyanuric Acid (CyA)
  • 9-18 oz. per 10,000 gallons provides 5-10 ppm available chlorine
  • FREE In-Store Water Testing - Find your local Leslie's Pool Store and get your FREE water test!
  • AccuBlue Home Water Testing - convenient, lightning fast and accurately measures 10 aspects of water chemistry. Learn more: Leslie's AccuBlue Home

When you have an algae bloom or need to treat other pool problems, look no further than Leslie's Power Powder Plus Cal-Hypo Pool Shock. With 73% Calcium Hypochlorite active ingredient and a minimum of 70% available chlorine, it's the strongest pool shock available. Power Powder Plus is known as a solution shock as it destroys algae blooms and organic as well as inorganic contaminants. Power Powder Plus Calcium Hypochlorite Pool Shock is also great for weekly maintenance to super chlorinate and give your chlorine levels a quick boost when you need it. Whether you're using Power Powder Plus as a treatment or maintenance pool shock, it's extremely effective at keeping pool water sanitized and safe for swimming.

Active Ingredient: 73% Calcium Hypochlorite

Leslie's Power Powder Plus Pool Shock has the highest percentage of Calcium Hypochlorite available for a super strength and concentrated pool shock. Some other pool shocks have a lower percentage of active ingredient with a higher percentage of inert ingredients which reduce the amount of chlorine sanitizer that is ultimately added to your pool.

70% Minimum Available Chlorine

With Leslie's Power Powder Plus , you get at least 70% available chlorine to kill and inactivate algae spores, bacteria, germs, and other water contaminants. Don't settle for anything less when looking for a pool shock to effectively treat pool problems like algae blooms and swimming accidents fast. As the chlorine dissolves in the water, it forms hypochlorous acid which is what kills and eradicates algae and bacteria.

Low Residue & Fast Dissolving
Fast acting and dissolving, Leslie's Power Powder Plus works quickly to kill algae and bacteria without leaving any noticeable residue behind. Even though it is a calcium based granular chlorinated shock, it won't significantly increase calcium hardness levels in the pool water. Power Powder Plus Calcium Hypochlorite shock works fast to eliminate contaminants currently in the water while preventing future potential algae growth.

Please Note: Depending on water chemistry levels such as high pH and Calcium Hardness, Cal-Hypo shock can cause possible turbidity or clouding of the water when added. This will normally clear up on its own.

Non-Stabilized Chlorine Pool Shock

There is no stabilizer or conditioner in Power Powder Plus Cal-Hypo Pool Shock so adding it will not raise cyanuric acid (CyA) levels in the pool water if they are already elevated. With this in mind, it's best to add during evening hours while the filter pump is running to reduce UV degradation from the sun.

Leslie's Power Powder Plus Cal-Hypo Pool Shock

To get rid of the toughest of algae and solve other pool problems fast, look no further than Leslie's Power Powder Plus. The highest percentage of Calcium Hypochlorite active ingredient to destroy organic contaminants, kill bacteria and control algae. At Leslie's, We Know Pools, and we are your best source for the strongest Calcium Hypochlorite pool shock.

Usage Directions for Swimming Pools:

  • Add the recommended dosage of Leslie's Power Powder Plus during the evening hours while the filter pump is running.
  • When adding to your pool, broadcast evenly over a wide area in the deepest part of the pool. Use a clean, dry scoop to measure this product. Do not use the scoop for any other purpose. If any granules settle to the bottom of the pool, use a brush to disperse.

Please Note: Packaging may appear different than image, but chemical contents are exactly the same.

Product Type: Pool Chemical
Chemical Type: Shock
Active Ingredient: Calcium Hypochlorite
Container Size: Bag: 1 lb
Manufacturer: Leslie's
Equivalent SKU: 14670

What does pool shock do?

Pool shock introduces a potent concentration of oxidizing agents, typically chlorine or similar compounds, to eradicate bacteria, algae, and other organic pollutants.

When should I shock my pool?

For optimal effectiveness, it is generally recommended to shock your pool at night. This allows the chlorine to work without interference from the sun's UV rays. Beyond your regular weekly maintenance, there are specific situations that necessitate additional shocking of your pool.

How often do I need to shock my pool?

A regular weekly maintenance schedule involves shocking or oxidizing the pool water each week, using either a chlorine shock or a non-chlorine shock based on the tested levels of chlorine. You may use a chlorine-based shock when chlorine levels are below 2 ppm, or a chlorine-free shock to oxidize contaminants in the water when chlorine levels are above 2 ppm.

How do you shock a pool?

  1. Test the Water: Using a water test kit or test strips, ensure that all aspects of water chemistry are within the proper range. Use non-chlorine shock if your Free Available Chlorine level is between 2.0–4.0 ppm, and use a chlorine-based shock if levels are below 2.0 ppm.
  2. Circulate the Water and Pool Shock: Turn on your pump and filter system to circulate the water. Then, following product label instructions for application, pour your shock around the inside perimeter of your pool. The best time to shock is at dusk or evening hours, so you can let your pump run overnight. Shocking the pool at night allows the shock to work most efficiently, without the sun burning off the chlorine quite as fast
  3. Wait for Free Available Chlorine (FAC) Level to Drop: If using a chlorine-based shock, continue letting the pump run for at least 6–12 hours, then retest the water. The Free Available Chlorine (FAC) level may still be very high, making it unsafe to swim.
  4. Enjoy Healthy, Clean and Beautiful Pool Water: Wait until the FAC level falls within the ideal range of 2.0–4.0 ppm before jumping back in the pool. Now, go enjoy your clear, clean, and safe swimming pool!


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