Increasing CYA

pablocruz23

Member
Mar 10, 2025
12
California
Last week, my pool test kit (Easytest Pool & Spa test strips) said that I had 0 cyanuric acid. Since then, I have gradually added about 8 pounds of CYA to my 20,000 gallon pool. Why so much? Because when I test the water, it still shows that I have 0 cyanuric acid.

The only effect I can see is that adding CYA has lowered my pH.

Is it the test kit?
Easytest Pool & Spa test strips

Is it the brand of CYA?
4 lbs Conditioner Stabilizer for Swimming Pools Cyanuric Acid by Nu-Clo 1306
Another 4 lbs of Pool Mate Premium Pool Stabilizer and Conditioner, Concentrated Cyanuric Acid for Pools

Is it the method I'm using? I stir up some CYA in a 5 gallon bucket. Then I slowly pour it into the skimmer.
 
Hey Pablo and Welcome !!!!


We call them guess strips for a reason. Even *if* it was accurate, it's way too vague for the CYA values it provides.

Have a read :
Test Kits Compared

And some others :
Pool Care Basics
FC/CYA Levels
PoolMath

You're also probably trapping it in the filter when you pour it in the skimmer and it may take a week to dissolve.

 
The 8 pounds you have added will/has raised the CYA by 50 ppm.

Unless you just filled this pool with fresh water, you likely did not start at 0.

Do NOT add any more stabilizer.


Ok. Should I just accept that surely there must be enough CYA? My test strips say I've got 0.
Or is it a known thing that Easytest Pool & Spa test strips can't accurately detect for CYA? Perhaps there's a test kit that can detect CYA?
 
You cannot manage pool water chemistry without a proper test kit. See messages above.
 
TFTestkits.net
The kits they sell are the best value. You need the tests to manage your pool water chemistry.
Depending on where you live in California, Calcium Hardness and TA can be an issue from fill water and evaporation.
Do not cheap out on testing. It will cost you many 100X as much in chemicals and mistakes.

You are currently in a position that you likely will be draining a significant volume of your pool water due to the false data you are getting from the guess strips.
 
There are only two test kit recommended here. Taylor Technologies test kits are the gold standard.

You don’t have to buy either from tftestkits.net You can buy the
Taylor K-2006 from Amazon for approximately $75-80. However at that price point you will be getting the small sized test kit and then have to buy replacement reagent very soon.
 
TFTestkits.net
The kits they sell are the best value. You need the tests to manage your pool water chemistry.
Depending on where you live in California, Calcium Hardness and TA can be an issue from fill water and evaporation.
Do not cheap out on testing. It will cost you many 100X as much in chemicals and mistakes.

You are currently in a position that you likely will be draining a significant volume of your pool water due to the false data you are getting from the guess strips.
Thank you!
 

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The kit is mostly setting you up with the parts to perform the tests. Like the included $45 stirrer in the TFpro / TFpro salt that is a must have.

Once you have the parts, the refills go on sale each March for mid $40s and it's much easier to swallow.
 
Last week, my pool test kit (Easytest Pool & Spa test strips) said that I had 0 cyanuric acid. Since then, I have gradually added about 8 pounds of CYA to my 20,000 gallon pool. Why so much? Because when I test the water, it still shows that I have 0 cyanuric acid.

The only effect I can see is that adding CYA has lowered my pH.

Is it the test kit?
Easytest Pool & Spa test strips

Is it the brand of CYA?
4 lbs Conditioner Stabilizer for Swimming Pools Cyanuric Acid by Nu-Clo 1306
Another 4 lbs of Pool Mate Premium Pool Stabilizer and Conditioner, Concentrated Cyanuric Acid for Pools

Is it the method I'm using? I stir up some CYA in a 5 gallon bucket. Then I slowly pour it into the skimmer.
Also - what is the pool water temp? CYA is one of the tests that's way off if the water is too cold.
 
Once you get your test kit, let the pool water sample warm to normal room temperature, 70F or higher, before performing the CYA test.
 
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Follow-up: I bought the Taylor test kit recommended above and have discovered that yes, my CYA levels are very high.

Is the recommendation to drain the pool part way and fill it with fresh water? How much of the pool needs to be drained? Can I do it in phases?
 
my CYA levels are very high.
We need a # to know how much to drain.
Can I do it in phases?
Multiple drains lose efficiency removing good water with the bad. For example, two 50 % drains only remove 75% of the water. The third 50% drain removes half of the remaining 25% of old water. So you'd drain 30,000 gallons and still have 12.5% of the original water.

See both draining and no drain exchange in the link below.

 
We need a # to know how much to drain.

Multiple drains lose efficiency removing good water with the bad. For example, two 50 % drains only remove 75% of the water. The third 50% drain removes half of the remaining 25% of old water. So you'd drain 30,000 gallons and still have 12.5% of the original water.

See both draining and no drain exchange in the link below.

I followed step 8 to determine that my CYA is between 160 and 180.

I'm hoping I don't have to drain the whole pool. Let me know what you think is the most painless approach to getting this CYA down.
 
How high? If over 90, do this test starting at #8
I followed step 8 to determine that my CYA is between 160 and 180.

I'm hoping I don't have to drain the whole pool. Let me know what you think is the most painless approach to getting this CYA down.
 

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