Not holding chlorine

[mrsk920]

We opened our above ground pool (10,000 gallons) Sunday, it was pretty clear and I was impressed. I scrubbed the walls and floor of the pool which clouded the water and ran the filter approx 9 hours.
I used a Taylor 2006 to obtain these readings.

Readings 6/23:
FC 0.5
CC 0.0
PH 7.8
TA 110
CYA 40
That night I added 68 oz of 6% bleach plus 2 - 3" tabs in a floater. Yesterday when I got home I got the readings below:
Readings 6/24:
FC 0.5
CC 0.5
PH 7.4
TA 90
CYA 40
Per Pool Math app I added 116 oz of 6% bleach last night and ran the filter overnight and this morning there was almost no chlorine left. Please help, this pool has been an issue the last 2 years with holding chlorine but last year the problem was a CYA of 100+..... FYI we drained half the pool when closing it and filled with fresh water when opening. Do I need to SLAM?

 

[mrsk920]

Are these readings wrong b/c I used a 10 ML sample during the FC/CC test and not the 25 ML ??

 

[mknauss]

You need to follow the SLAM Process.

Using the 10ml water sample is fine. That has all the accuracy you need.

 

[mrsk920]

Thank you. Slam FC target for CYA of 40 is 16 & it says to add 322 oz, I have read the SLAM process and please correct me if I am wrong. I need to keep adding bleach to maintain an FC of 16, running the filter continuously until FC holds and CC is 0.5 or less. Any idea how much bleach it will take to achieve this or how long I will need to keep adding it?

 

[mknauss]

First lower your pH to 7.2 with muriatic acid.

Correct on the SLAM level FC. Once you have the pH lowered, add the chlorine and maintain FC of 16 ppm by testing and adding several times per day. Run the pump 24/7 if possible. Brush often.

If the water is not green or super cloudy, it should only takes days not weeks. Your sand filter will take a while to clear the pool of debris. Remember that the first criteria for a successful SLAM is crystal clear water. Only when you have that, do you run the OCLT.

 

[CarolineM]

If you buy a stronger bleach/chlorine it won’t take as much. HD, Walmart and some farm supply stores carry 10%

 

[mrsk920]

Just wanted to share my success with you all! Completed the SLAM and Yes our water is so clear you can see the diving rings on the bottom! Finally! We have good results after 2 years of pool maintenance nightmares. If anyone else is having trouble please follow TFP pool school it works!

 

[zea3]

Thank you for your kind words! We are always happy to help!

 

[bmoreswim]

Just wanted to share my success with you all! Completed the SLAM and Yes our water is so clear you can see the diving rings on the bottom! Finally! We have good results after 2 years of pool maintenance nightmares. If anyone else is having trouble please follow TFP pool school it works!

That's fantastic! So happy to see another crystal clear pool.

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