CYA Way Too High

[waltonrosenthal]

Hello! To start, I am a NEW pool owner--we moved into a house with an above ground pool, and we are doing our best! We have a DE filter, variable speed pump, chlorine-sanitized. Approx 13k gallons.

Pool started out great this summer--crystal clear, good levels. We mostly chlorinate with stabilized tabs. We are also new parents, so we have like zero free time, but we try to skim/brush multiple times per week and we have a little robot vacuum that we run. After a VERY hot week, we noticed that the pool was starting to turn green and a little cloudy. When we brush the bottom, green dust definitely comes off (assuming green algae). We decided to try the SLAM process and bought a Taylor test kit. Tested for CYA--it was SO high that it didn't even make it to the 100 line before the black dot completely disappeared.

So I know the only way to lower CYA is to drain and dilute. Does anyone have recommendations for how much to drain at once? And what is a safe level to SLAM? As in, how low CYA do I need to start the SLAM process? Is there any wiggle room there?

And then of course, how do I keep this from happening again?!

Thank you so much, pool experts! We are really wanting to learn and maintain our pool properly, even if it requires a lot of work up front

 

[PoolStored]

I would lower your CYA to 40-60.

Do test #8 here and report back. CYA reduction is 1:1...so if you replace 50% of the water, it will lower CYA by half.

CYA - Cyanuric Acid Test

Cyanuric acid (CYA) is the chemical name for the product commonly called “pool water stabilizer” … Read more…

www.troublefreepool.com

As to water replacement, read "NO Drain Water Exchange" here:

Draining - Further Reading

www.troublefreepool.com

 

[pjt]

bought a Taylor test kit

Which model?

And then of course, how do I keep this from happening again?!

As you've proven to yourself, tabs aren't a sustainable way of chlorinating your pool. There are two viable options to long term chlorination: salt water chlorine generator (SWCG) or liquid chlorine (LC). I'd highly recommend a SWCG, which is very convenient and will save you much time, money, and effort over time.

 

[TinFoilHat]

You want the Taylor K2006 or a TF100 test kit. Those will have powder to do the proper chlorine tests.

 

[Ticojpunk]

I had a CYA of approx 100 the beginning is this season. I did the no drain method (drained with sump pump while refilled with the hose. Just ran it for a few hours and I’m now sitting very happily at CYA 40. Important to run your pump into a 5g bucket and time how long it takes to fill it. If it’s a minute for example you know your drain rate is 5g/minute, then calculate how long you need to do it. Pretty sure that’s all in that link posted earlier. It sure helped me out at the time.