CYA low. No Chlorine

amraney

Well-known member
Jun 7, 2019
73
Oklahoma
My pool is crystal clear but noticed I've had to add more chlorine lately. I tested today and here are my readings.
FC=0
CC=0
TC=0
PH=8+ Maybe like 8.2
TA=140
CYA= I filled it to the very top of tube and the dot disappeared. So like 20-25?
What should I add/adjust first and what/ where do I get the stuff to raise CYA?
 

frogabog

Gold Supporter
LifeTime Supporter
Jul 16, 2010
2,833
Portland, Oregon
You should be able to find CYA at Walmart, or Home Depot, or at a pool store. Dry Stabilizer is what it is commonly labeled as. Or, it can be ordered online. Amazon has the Chlorox brand for a little over $14 on Prime.

For now, you need to add chlorine though. That would be first.
Use Pool Math and calculate how much for 30ppm CYA if you feel it could be interpreted as 25. Anything reading over the line is rounded up to the next 10.

Assuming you want to raise your CYA to 40ppm, I'd say start with trying to do 5ppm and then check CYA after 24 hours. If it tests at 30, then add 10 more.

The CYA will lower your pH a bit, Pool Math will give you an estimate. After you add the CYA 2 times, you may be right where you need to be with pH.

At minimum, you'll then know how much acid you need to lower pH and TA with the acid and aeration method.
 
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Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
I would agree that you really need to get the CYA up via the sock method right away. More chlorine too. In this heat, the longer you wait the more potential for the water to get cloudy or green (algae). See FC/CYA Chart If you use bleach, remember it must be regular/plain - nothing scented or splashless. I would still pick-up a couple gallons of muriatic acid (MA) for the pH. Nothing works as fast and good as MA on pH. Keep that pH in the mid-7s as best as you can, and always store the MA in a separate container away from any other chemical, children, or pets. It's fine in the heat outside and away from everything & everyone.

Adding CYA:
To increase CYA via granular stabilizer, place the required amount as calculated by the Poolmath calculator into a white sock and place in the poolside skimmer basket. For those concerned about suction flow to the pump, suspending the sock near a return jet or from a floating device will also suffice. Best never to allow undissolved granules to rest directly against the pool surface. Squeeze the sock periodically to help it dissipate. Once dissolved, consider your CYA adjusted to that programmed (target) level. CYA test readings should show a rise in 24-48 hours, however some pools may experience a longer delay to fully register. Best to confirm final CYA in about 5-7 days before adding any more stabilizer/conditioner.
 
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amraney

Well-known member
Jun 7, 2019
73
Oklahoma
You should be able to find CYA at Walmart, or Home Depot, or at a pool store. Dry Stabilizer is what it is commonly labeled as. Or, it can be ordered online. Amazon has the Chlorox brand for a little over $14 on Prime.

For now, you need to add chlorine though. That would be first.
Use Pool Math and calculate how much for 30ppm CYA if you feel it could be interpreted as 25. Anything reading over the line is rounded up to the next 10.

Assuming you want to raise your CYA to 40ppm, I'd say start with trying to do 5ppm and then check CYA after 24 hours. If it tests at 30, then add 10 more.

The CYA will lower your pH a bit, Pool Math will give you an estimate. After you add the CYA 2 times, you may be right where you need to be with pH.

At minimum, you'll then know how much acid you need to lower pH and TA with the acid and aeration method.
I will go pick that up. Thank you, i wanted to get on top of this asap and appreciate your help.
 
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amraney

Well-known member
Jun 7, 2019
73
Oklahoma
I would agree that you really need to get the CYA up via the sock method right away. More chlorine too. In this heat, the longer you wait the more potential for the water to get cloudy or green (algae). See FC/CYA Chart If you use bleach, remember it must be regular/plain - nothing scented or splashless. I would still pick-up a couple gallons of muriatic acid (MA) for the pH. Nothing works as fast and good as MA on pH. Keep that pH in the mid-7s as best as you can, and always store the MA in a separate container away from any other chemical, children, or pets. It's fine in the heat outside and away from everything & everyone.
I have bleach (plain 10%) and MA on hand but wasn't sure about CYA. I so don't want my pool to turn green or cloudy. The TFP way of taking care of my pool has been so easy and want to stay on top of every little thing. Thank you for your help!