So I think we need to slam our pool?

amch17

Member
Mar 2, 2019
10
Cypress TX
Chlorine has not been lasting at all! I read the "Slamming your pool" article, but still have a few questions.
Here are our test results today.
CYA 30
FC 0.8
CC 1.2
PH 8.0
TA 70
CH 250

My question is, when adding the chlorine suggested by the PoolMath app, how often is it suggested that we test? How often do we keep adding chlorine? We continue SLAMming until we pass an overnight test, correct? After that, when is it safe to swim in the pool?

Our pool is about 20,000 Gal, we use liquid chlorine.
 

gonfishin

Gold Supporter
Jun 13, 2017
279
Rochester, MN
It's safe to swim in the pool when

  • chlorine is above the minimum for your CYA (for 30, that is 2)
  • chlorine is less than SLAM level for your CYA (for 30, that is 12)
  • you can see the bottom of the deepest part of your pool

As far as testing frequency, as often as you can but at least 3-4 times per day during the SLAM. The more often you can test and add chlorine, the quicker you'll complete the SLAM. Don't forget to brush and vacuum frequently too. Brushing breaks the biofilm algae creates to protect itself. Vacuuming gets the dead algea out of the pool (and other stuff).
 
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amch17

Member
Mar 2, 2019
10
Cypress TX
We slammed and tested/adjusted every 2 hours. Last night about 40 min after last adjustment the FC was 13, this morning it was right at 12.
6 hours later it is at 5.6, is this normal?

Thanks in advance!


It's safe to swim in the pool when

  • chlorine is above the minimum for your CYA (for 30, that is 2)
  • chlorine is less than SLAM level for your CYA (for 30, that is 12)
  • you can see the bottom of the deepest part of your pool

As far as testing frequency, as often as you can but at least 3-4 times per day during the SLAM. The more often you can test and add chlorine, the quicker you'll complete the SLAM. Don't forget to brush and vacuum frequently too. Brushing breaks the biofilm algae creates to protect itself. Vacuuming gets the dead algea out of the pool (and other stuff).
 

amch17

Member
Mar 2, 2019
10
Cypress TX
I should add that we are in Houston and it is hottttt. The pool gets direct sunlight pretty much all day, partial shade starting at 6 pm.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
The large FC drop in the past few hours is a bit excessive. We know FC at SLAM level will drop faster than if it was at the regular "target" levgel of say 5-7. With a low CYA of 30 in our heat, the FC will also drop faster. But honestly what you are going through is a tough call. On one hand you seem to have passed your OCLT, but in post #1 you had an elevated CC level which is indicitive of algae or something being consumed.

I would continue wiht the SLAM Process today and perform another Overnight Chlorine Loss Test this evening. When you do your tests today and tomrorrow, make note of the CC as well. Tomorrow morning if you are sure to pass all 3 SLAM criteria (clear water, OCLT with no more than 1 FC drop, and CC no more than 0.5) then you should be good. At that point you could add stabilizer to get the CYA closer to 50 which should help preserve your FC better. I had to add stabilizer last week as well.
 
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amch17

Member
Mar 2, 2019
10
Cypress TX
The large FC drop in the past few hours is a bit excessive. We know FC at SLAM level will drop faster than if it was at the regular "target" levgel of say 5-7. With a low CYA of 30 in our heat, the FC will also drop faster. But honestly what you are going through is a tough call. On one hand you seem to have passed your OCLT, but in post #1 you had an elevated CC level which is indicitive of algae or something being consumed.

I would continue wiht the SLAM Process today and perform another Overnight Chlorine Loss Test this evening. When you do your tests today and tomrorrow, make note of the CC as well. Tomorrow morning if you are sure to pass all 3 SLAM criteria (clear water, OCLT with no more than 1 FC drop, and CC no more than 0.5) then you should be good. At that point you could add stabilizer to get the CYA closer to 50 which should help preserve your FC better. I had to add stabilizer last week as well.
Thank you so very much, the water is crystal clear and the CC was 0.2 earlier today, but I will continue to SLAM today and hope that the problem is solved by tomorrow.
 
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