Pool Shock Power Blast (68% Cal Hypo) 48x1 Lb Bag - R20841-48



Model # R20841-48

  4.75 Average  



Model # R20841-48

Alternate Part #'s 71428

Product Description

Cal-Shock 65  

Power Blast Cal Shock 65 is 68%CalciumHypochlorite with 65% available chlorine. Our best selling shock treatment, Cal Shock 65 is in a fast dissolving granular form so it quickly destroys organic waste, algae and bacteria saving you time and money. 
  • 1 lb bags Calcium Hypochlorite
  • Powerful shock treatment great for spring start up
  • Gives quick chlorine boost
  • Ensure pool water is balanced for best results
  • Complete instructions for dosage on container
  • Compares To BioGuard Burn Out
Pool Volume in gallons Amount of Shock needed weekly if pool is clear Amount of shock needed if pool is green
10,000 gallons 1 lbs. 2 lbs.
20,000 Gallons 2 lbs. 4 lbs.
25,000 Gallons 2.5 lbs. 5 lbs.
30,000 Gallons 3 lbs. 6 lbs.
35,000 Gallons 3.5 lbs. 7 lbs.
40,000 Gallons 4 lbs. 8 lbs.

*Always follow the manufacturer's recommendations/directions located on the product container.Store any un-open bags in a cool and dry location
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Product Specifications

# of 1 lb Bags:

?     Asked on 3/25/2020by Mary Ann Jaeger

can this be used as a sanitizer for bacteria?

A  Answered on 3/25/2020 by InyoPools Product Specialist Hector F.

Yes, this pool shock is considered a swimming pool water sanitizer. Please use this with chlorine tablets to maintain a healthy sanitation level in the pool water. 

?     Asked on 4/14/2015by John

What is the time limit to wait to swim with this shock

A  Answered on 4/14/2015 by InyoPools Product Specialist Joe S.

Make sure to keep the pump and filter running during application and for at least 6 to 8 hours after application to allow for the best product dispersion. You should always test prior to swimming to make sure water levels are safe.

?     Asked on 2/14/2015by Mark Westphalen

I have used PoolStyle Bright Shock for the past 2 years. It is a 1 lb package and is 29% Lithium Hypochlorite and 71% Other Ingredients. Is Pool Shock Power Blast similar or should I look for something else.

A  Answered on 2/16/2015 by InyoPools Product Specialist Andy O.

Mark,If the shock you are using has 29% lithium hypochlrite, this Power Blast will be more than twice the power and available Chlorine at 68% calcium hypochlrite.

?     Asked on 12/20/2012by Guest

I think I have a chlorine lock in my swimming pool. How did I get it and how can I get rid of it?

A  Answered on 12/20/2012 by InyoPools Product Specialist Patrick P.

Chlorine lock is a condition in your swimming pool when the chlorine levels ( free chlorine and total chlorine) are not the same which makes the chlorine useless. You can read more here.

?     Asked on 10/25/2012by Guest

My swimming pool is clear but when my kids and I went swimming, our eyes burned. My neighbor came by and checked and said that the pool should be fine because he can smell the chlorine. What is wrong with my pool?

A  Answered on 10/25/2012 by InyoPools Product Specialist Patrick P.

It sounds like you have chloramines. Chloramines are formed any time ammonia and nitrogen are in the water. Chloramines smell bad and cause skin and eye irritation. You can resolve the problem using this method.

?     Asked on 10/25/2012by Guest

Is it true that if I have a vinyl pool I can only use liquid shock?

A  Answered on 10/25/2012 by InyoPools Product Specialist Patrick P.

You can use granular or powdered shock with a vinyl pool as well. Before adding the shock to the pool, you want to add it to a bucket of pool water to pre-dissolve it.

?     Asked on 10/19/2012by Guest

No matter how much chlorine shock I put in my pool the chlorine level is always low. What can I do?

A  Answered on 10/19/2012 by InyoPools Product Specialist Patrick P.

I would first make sure that you are testing the total chlorine AND free chlorine. If they are not the same reading, you may have a chlorine lock. If the chlorine levels are the same, I would check the pH, alkalinity and cyanuric acid levels.

?     Asked on 1/25/2012by Guest

I'm looking for pool shock to sanitize my drinking water. Will this work?

A  Answered on 1/25/2012 by InyoPools Product Specialist Patrick P.

I have heard of people using pool shock to sanitize drinking water but I can not promote the use of any pool shock for this purpose. You will want to contact the NSF for further information.


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