Model # R20841-12

Alternate Part #'s LZA71428A

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
For More Pool Chemicals

Product Specifications

# of 1 lb Bags:
Chlorine Shock

?     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.

?     Asked on 10/12/2012by Guest

I tested my chlorine levels and they were at 0, so I shocked it. This didn't bring the levels up at all. What could be the problem and what should I do?

A  Answered on 10/12/2012 by InyoPools Product Specialist Patrick P.

If your chlorine level remained at 0 after shocking, I would recommend checking the pH, alkalinity and cyanuric acid levels. I would also recommend checking the available chlorine percentage on the pool shock.

?     Asked on 10/18/2012by Guest

I have an in ground vinyl swimming pool and usually use liquid shock. I have heard that the granular shock is better but it's not for vinyl pools. Is there another type of shock that I can use that is stronger than the liquid?

A  Answered on 10/18/2012 by InyoPools Product Specialist Patrick P.

You can use the granular shock but I would recommend adding it to a bucket of pool water to pre-dissolve it then pouring it along the perimeter of the pool.

?     Asked on 10/25/2012by Guest

My pool company uses liquid shock in my pool. Is this granular shock any better?

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

Yes. If you look at the labels of both products, you will find that liquid shock is weaker. The bottle has vented caps (to vent chlorine gas) so the longer it sits on a shelf, the weaker it gets. Granular shock is a lot stronger and does not lose its strength as long as it's stored properly.

?     Asked on 10/25/2012by Guest

Why do I need to shock the pool if I use chlorine tablets?

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

Chlorine tablets alone are not enough to keep the water sanitized. Pool shock helps to oxidize the water as well as breakdown chloramines.


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