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MODEL#R20841-6
(4.65 out of 5 Stars on 31 Ratings) Ask us a question regarding R20841-6
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*Always follow the manufacturer's recommendations/directions located on the product container.Store any un-open bags in a cool and dry locationFor More Pool Chemicals
Zappit MSDS (95.03 KB)
Please feel free to view our complete library of owners manuals.
How To Winterize Your In-Ground Pool
How To Keep Your Pool From Turning Green While You're Away
How To Break Chlorine Lock
12/20/2012
Q:I constantly have an algae build up in one corner in my swimming pool. What can I do to get rid of it?
A:I would recommend aiming the return fitting downward and towards the steps. This should help circulate the water around the steps better. I would also recommend brushing down the pool and using a chlorine shock.
10/25/2012
Q:When is the right time to shock my swimming pool?
A:A swimming pool should be shocked every 7-10 days. It is recommended to shock the pool during the evening hours so that the sun doesn't burn off the chlorine.
Q:Is it true that if I have a vinyl pool I can only use liquid shock?
A: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.
10/18/2012
Q:My pool company recommends using a phosphate remover. Do you have any such item?
A:I would recommend using Phosfree. The product container has easy to follow directions and will help you eliminate your phosphate problem.
Q:I have an in ground pool with a mesh winter cover. Several weeks ago, I had added 2 gallons of chlorine to the pool. Since then, with the mesh cover still on, the water has turned green. I've been adding about a gallon of shock each week without improvement. Should I continue adding shock to the pool or should I wait?
A:I would recommend waiting until the pump and filter are running again before adding any more shock to the pool. Algae needs two things to grow: food and light. With a mesh winter cover, the algae has more than enough light to grow regardless of the shock that you're putting in. Also, shocking the pool without circulation can cause bleaching of the pool surface
10/12/2012
Q:Can I add shock through my automatic chlorinator?
A:No, you should never add shock through an automatic chlorinator. Never mix different types of chlorine. Pool shock can be added to a bucket of water and poured directly into the swimming pool.
2/10/2012
Q:I just purchased a new pool. What chemicals do I need to keep it clean?
A:Congratulations on your pool purchase. To keep your pool nice and clean you will need a variety of chemicals. Feel free to browse through our Pool Chemical Guide. It provides quite a bit of information to help get you started.
1/31/2012
Q:Can I pay for expedited shipping on my pool chemicals?
A:It is the policy of our shipping carrier, UPS, to not permit expedited shipping of possible hazardous or dangerous chemicals via air transit. This policy includes all pool chemicals making the only available delivery method for such items UPS Ground.
1/25/2012
Q:I'm looking for pool shock to sanitize my drinking water. Will this work?
A: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.
Ratings Summary
Average Rating: (4.65 out of 5 Stars)
Recommended: (97%) 30 of 31 customers would recommend this product to a friend.
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The Most Helpful Review
3 of 3 people found the following review helpful:
(4 out of 5 Stars) Get ready for economic collapse :)
Reviewed By: Mike from MA (10/5/2011)
Purchased this product for drinking water purification. Good price for what I was looking for. Make sure you know how to use this stuff if you're planning to use it for drinking water.
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The Most Recent Reviews
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(5 out of 5 Stars) Best pool Shock on the market
Reviewed By: Robert M. from Southington, Ct (7/6/2012)
Pros: Fast desolving
I am happy I switched to Zappit Pool shock, it out performs all the others.
(4 out of 5 Stars) Great pool shock
Reviewed By: Izzy from Woodbridge, VA (5/30/2012)
Pros: works great!
shock works great. it was delivered very fast too! will buy again.
(5 out of 5 Stars) Great way to start opening your pool!
Reviewed By: Great replacement part from Arab, AL (4/6/2012)
Extremely fast shipping!
(5 out of 5 Stars) Great Pool Cleaner
Reviewed By: Jody N. from Manton, MI (3/16/2012)
Pros: Individually packaged in one pound. Easier to store.
Awesome product and shipping was very quick. You can not get this high of a quality product at the big box stores.
(5 out of 5 Stars) Clear as crystal
Reviewed By: Robert R. from San Diego, CA (12/17/2011)
Pros: water clarity
My personal standard for water clarity is my dime test. I have a dime epoxied to the bottom of the deep end of the pool. If I can clearly see the face on the dime, then the water is clear. Zappit Pool Shock gets the job done using less shock than other brands. Costs less, too.
(5 out of 5 Stars) Excellent Swimming Pool Cleaner
Reviewed By: David C. from Muncy, PA (11/17/2011)
Pros: Easy to use
This pool shock worked very well for me and I would highly recommend it.
(5 out of 5 Stars) Quick service
Reviewed By: from Chico, CA (9/27/2011)
Cal Hypo arrived as promised, and in a timely manner. No complaints!