16000 gal vinyl liner pool, just had 2nd liner put in this spring after 15 years. Having problem keeping chlorine levels steady. Ph also creeps up after a few days. My alk is 121,,,CH a little low at 144...CYA steady at 45. I use liquid chlorine as the tabs raise the CYA over time. Never had this issue before once I got levels balanced at start up no issues thru the summer. Any ideas out there Problem is chlorine does not hold even for 24 hrs Ph climbs even though ALK is ok????
lo chlorine high ph
- Thread starter buckster3530
- Start date
- May 3, 2007
- 18,097
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Most likely reason CL drops is because of algae. Have you tried a Overnight Chlorine Loss Test.
But you really have not given us much to go on. We need a full set of test results (not "everything is ok"). Also, please read these forum requirements:
www.troublefreepool.com
www.troublefreepool.com
Also, are you really in the industry or did you click that by mistake?
But you really have not given us much to go on. We need a full set of test results (not "everything is ok"). Also, please read these forum requirements:
Read This BEFORE You Post
We'd like to give you a few basic pointers of items that will help us, help you. From filling out a signature to posting test results.
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Also, are you really in the industry or did you click that by mistake?
Last edited:
no not in the biz, sorry my mistake see if i get this right 16000 gal. in ground vinyl liner pool. Hayward 36sq ft DE filter Hayward 1,5 hp single speed pump, run it 24/7. Readings this am....chlorine "LO", not enough to register on my Lamotte Color Q. or Lamotte test strips. PH was 8.4, ALK 121, CH was 144, CYA is 45. I shock after heavy rain or bather load. No visible algae, I apply algicide in small amounts weekly. Pool is southern exposure , full sun all day, water is crystal clear. Vac regularly do not allow any debris buildup. My 19th year with the pool and I have pretty musch seen it all thus the reason I am stumped.Thanks in advance, I will fix my profile
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You should consider getting a more reliable test kit as that’s likely what’s leading you astray. The TF-100 TFP recommends or the Taylor K2006C are recommended by TFP. In addition, what algaecide are you adding? That can have an effect on chlorine levels. TFP doesn’t recommend regular use of algaecide as it’s not necessary.
- Mar 5, 2020
- 3,221
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
Regarding the pH-rise despite Alkalinity being "OK": It is a common misconception to think that high Alkalinity means more stable pH.
Yes, alkalinity buffers against pH drops. But the buffer system used in pools is a Carbonate buffer (by adding bicarb). This means that the pool is oversaturated with dissolved CO2, which wants to outgas (like a soda bottle that is left open or nearly empty). This outgassing process comes with a pH rise (flat soda water tastes less acidic).
TA around 100 is required when using acidic chlorination methods like trichlor pucks. When using non-acidic chlorination methods (liquid chlorine or SWG), a lower TA around 60-80 usually results in a more stable pH (less rise), while still providing enough buffering. Just don't let TA drop below 50.
Make sure to do your own testing as mentioned above. Pool Store tests are not only unreliable, they also often report "adjusted" Alkalinity, which is garbage. Adjusted Alkalinity is only required as a proxy for the Carbonate content when calculating the Calcium Carbonate Saturation Index, it should not be reported to customers.
Yes, alkalinity buffers against pH drops. But the buffer system used in pools is a Carbonate buffer (by adding bicarb). This means that the pool is oversaturated with dissolved CO2, which wants to outgas (like a soda bottle that is left open or nearly empty). This outgassing process comes with a pH rise (flat soda water tastes less acidic).
TA around 100 is required when using acidic chlorination methods like trichlor pucks. When using non-acidic chlorination methods (liquid chlorine or SWG), a lower TA around 60-80 usually results in a more stable pH (less rise), while still providing enough buffering. Just don't let TA drop below 50.
Make sure to do your own testing as mentioned above. Pool Store tests are not only unreliable, they also often report "adjusted" Alkalinity, which is garbage. Adjusted Alkalinity is only required as a proxy for the Carbonate content when calculating the Calcium Carbonate Saturation Index, it should not be reported to customers.