Excessive Chlorine Demand

Aug 18, 2017
3
TX
I’m having trouble keeping chlorine in my three year old Pool. My CYA was very high, so following advice from TFP app I drained about 80% of my water and started again. My CYA reading is still reading over 160, we’ll above the recommended 30-40. I’ve been told that instead of acting as a stabilizer, excessive CYA does the opposite and eats up the chlorine. I believe this is what’s happening in my pool. The Pool store guy said it’s likely that CYA has leached into my plaster and that only an acid wash would allow me to return to acceptable levels. In the meantime he wanted to sell me non stabilized tablets at $90 a pop. Wondering if I could get some insight and comments on my problem or if I should just buy the local Chlorox Bleach plant. Thanks a lot.
 
Welcome to the forum!

CYA does not leach into the plaster.

Non stablized pucks are cal-hypo with a polymer sticking it together. Do not use those. Use Liquid chlorine.

How are you testing? IF the current CYA is 160, you need to do another 75% drain and refill.

Please add your test kit name/model to your signature.

Take care.
 
Hi. Testing with TF-100 kit whose CYA reading is over 100. Pool store said 160. Should I just go ahead and replace all the water? Took out at least 75% a month ago. No residual CYA on Pool walls then, correct?

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My CF readings are always zero. Adding about 3-4 gallons of bleach a week as well as a couple bags of shock