New member

Apr 20, 2018
15
0
Acworth/GA
#1
I have had an ongoing issue with high CYA levels in my pool 150-175ppm. I have recently drained 1/3 of the water and refilled. I also switched from using tri-chlor 3"tabs to sanitizing with liquid chlorine (8.25%). The CYA has been reduced to 80ppm. My question is, if I do nothing more and continue to use liquid chlorine, will the CYA stabilize and hold steady at 80ppm. I intend on draining and refilling some more to get to 40-60 ppm CYA.
 

triptyx

TFP Guide
Apr 12, 2016
1,485
0
Tucson, AZ
#2
Correct. CYA is only present in stabilizer products, trichlor, and dichlor (the last two are commonly sold a chlorine in the form of granular shock and puck products). It is very slowly consumed over time (usually 3ppm or so a month), and is not present in liquid chlorine or bleach.

So for now, at 80ppm of CYA, based on this chart - Pool School - Chlorine / CYA Chart , add enough bleach to get your FC level to 11ppm each day, and make sure FC never ever drops below 6 and you'll be in great shape!

You can use the PoolMath link at the top of this page to enter your pool volume, bleach/chlorine strength, and it will tell you how much to add to reach 11ppm.