Model # R20841-24
Alternate Part #'s LZA71428A
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.
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I'm looking for pool shock to sanitize my drinking water. Will this work?
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.
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?
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.
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?
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.
No matter how much chlorine shock I put in my pool the chlorine level is always low. What can I do?
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.
My pool company uses liquid shock in my pool. Is this granular shock any better?
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.
(5 out of 5 stars) Works great at a great price
Reviewed By: Noah R. from fort lauderdale ()
Pros: Works well, dissolves fast, good price
This is a great low price for 68% Cal Hypo. It dissolved fast and works great. I sometimes skip shocking my pool because of the price of shock or because I've run out. After getting 2 boxes of this shock I'm sure my pool will be looking better than ever.
(3 out of 5 stars)
Reviewed By: dnpcov from Vacaville, CA ()
FYI, when I received the order it was delivered in a crushed box. The contents were scattered all over and not very secure. Good pricing, good product, Very poor shipping Also, I did not receive the Cal-Shock 65 product which I used last year. I received "Zappit". I am hoping it will perform the same.
(4 out of 5 stars) Good product but not that price competitive
Reviewed By: David G. from Houston, TX ()
Pros: Ease of ordering. Shipping is slightly more than sales tax locally.
Cons: Not price competitive for an on-line product.
Works as well as anything I've bought at retail but I've since found comparable products on sale locally for the same or less.