Chlorine keeps going to Zero


Aug 29, 2016
Hi all,
I have a 8500gal AGP Intex 12x24 ultra frame with newly filled water from faucet. So regular water with sand pump.

I am having trouble retaining Chlorine. Pool is crystal clear in 68’F and run pump for 6hrs daily.

I have shocked almost daily. For example I shocked Fri night only to have zero chlorine sat afternoon. Shocked again Saturday night with no chlorine by Sunday afternoon . Shocked again Sunday night to discover no chlorine by Monday afternoon. In between I have a solar cover and little use.
Have 2 tablets in a tablet floater also newly added Friday.
Trip to Leslies water test this afternoon . Store Owner advises me to use his Chlorine Plus (75%) and run pump for longer for 8hrs instead of 6hrs.

free chlorine 0.5
Total chlorine 0.5
pH 7.4
Total alkalinity 110
Calcium Hardness 230
Cyanuric Acid 30
Iron 0
Copper 0
phosphates 0

Sand filter is reading green approaching yellow pressure.

Any advice as I’m surely shouldn’t be having shock every day??

Thanks in advance


Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
Laughlin, NV
First is to get your own test kit. I suggest the TF-100 A proper test kit is needed to get the accurate water chemistry results needed to follow the TFP protocols.

Second, you do know you have to add chlorine every day, right? The tablets you added are OK but I would not add any more. Follow the FC/CYA Chart and add liquid chlorine each evening to get the FC to within the target range.

I doubt you need to run your pump longer. ABG pools can have circulation issues. Brush it once a day until you are swimming in it every day.
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Mod Squad
TFP Expert
Apr 4, 2007
SW Indiana
The floater is just not going to add chlorine to the pool fast enough to keep up with sun loss and consumption from biological contaminants, especially running the pump only 6 hours. Use liquid chlorine or plain laundry bleach for chlorination and add and check a few times a day until you get a handle on how much your pool uses.
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Aug 29, 2016
Thank you for above. I have the test kit from Tfp. I am comfortable doing Chlorine and pH but not the others yet and let Leslies do it for me for now.

I bought liquid chlorine. Shocked with granules Sunday with a higher strength chlorine 75%, that seems to stayed until today, Wednesday. I just added liquid chlorine from THD. Will see tomorrow how that sticks.

So I’m really clear, even with tablets in pool, I should expect to add chlorine everyday?Thx


Silver Supporter
In The Industry
Aug 15, 2017
Spring Valley, NY

A few things to keep in mind.
A) It's either TFP or pool store but the two won't mix well here.
B) You absolutely have to decide who you follow. If you keep putting chems in the pool we don't back we aren't going to be helpful to you. You need to follow and it'll end with a pretty water but it takes patience.
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