View Full Version : How much liquid pool shock should I use in a 12k gal pool??
Booter
06-06-2018, 03:52 PM
The liquid pool shock I purchased is 10% sodium hypochlorite. Label on it reads: "Every seven days, or as necessary, superchlorinate the pool with 54 to 108 oz. of this product for each 10,000 gallons of water to yield 5 to 10 ppm available chlorine by weight.
My pool has 12,500 gallons of water. How many ounces should I use? Thanks.
PoolDoc
06-06-2018, 06:07 PM
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12,500 gallons => 9.6 PF
10% shock => approx 0.8 lbs chlorine (gas equivalent)
0.8 x 9.6 = 7.7 ppm
By the way, "shock" is not a thing, just an action. "Shocking" just means adding more chlorine than usual . . . and there's no magic number.
Well, there is, but it's not a SINGLE number.
Rather you should maintain your chlorine level at 5% of whatever your stabilizer level is. So, if CYA=30 ppm, then FC should be 1.5 ppm AND if CYA= 80 ppm, then FC should be 4 ppm
"Shocking" -- as an action, rather than a chemical -- will help kill off algae and slime that may be getting started in corners, etc. In CLEAR water, with no problems, a weekly dose of 15% of CYA is a good idea (5 ppm if CYA=30; 12 ppm if CYA = 80).
AND . . . if you add it in the evening, you'll get much more 'bang for your buck'.
PS. At many Walmart stores you can buy 10% "Pool Essentials Chlorinating Liquid (https://www.walmart.com/ip/48938023)" for $3.27. And it's probably fresher than what the pool store has!
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Booter
07-05-2018, 07:04 PM
12,500 gallons=>9.6 PF
10% shock => approx 0.8 lbs chlorine (gas equivalent)
0.8 x 9.6 = 7.7 ppm
2 questions:
1. What is PF?
2. Is 7.7 ppm the chlorine that the 1 gallon of 10% sodium hypochlorite will add to my 12,500 gallon pool?
PoolDoc
07-06-2018, 07:20 AM
2 questions:
What is PF?
Is 7.7 ppm the chlorine that the 1 gallon of 10% sodium hypochlorite will add to my 12,500 gallon pool?
PF is the ratio between your pool and a pool with 1,000,000 lbs of water (~120,000 gallons). The calculation of the dose effect on a pool is:
PF x %Concentration x Pounds
Yes. 1 gallon of 10% bleach is ~ 0.8 lbs of 100% chlorine equivalent, and will add 7.7 ppm of chlorine to a pool with a PF of 9.6.
For example, with 2 lbs of dichlor, the calc would be
9.6 x 55% x 2 = 10.5 ppm FC
. . . and . . .
9.6 x 50% x 2 = 9.6 ppm CYA