Runaway CYA?

[eagle47]

After being near rock-solid stable all summer, my latest CYA readings are increasing dramatically:
8/21: 35
8/22: 35
8/23: 40
8/24: 45
8/25: 45
8/26: 50
8/27: 60

What could be the cause? The only chemical additions I've made during this time are a half-gallon of LC every night as per my usual regime.
FC: 6.0
TC: 6.0
pH: 7.4
TA: 90

 

[Texas Splash]

When was the last time you added stabilizer, and how did you add it? Was it fully dissolved (sock method) or something else?

 

[eagle47]

Added stabilizer after pool opening (late May) per sock method.

 

[YippeeSkippy]

No granular chlorine products added? Any pucks??

Maddie

 

[Texas Splash]

Added stabilizer after pool opening (late May) per sock method.

Then that indeed is very odd. We know new water has no CYA, so unless someone used tabs, powders, or some sort of stabilized product, the only thing left is testing error. Odd indeed.

 

[eagle47]

No granular chlorine products added? Any pucks??

Maddie

No, no other products of any form.

 

[eagle47]

Then that indeed is very odd. We know new water has no CYA, so unless someone used tabs, powders, or some sort of stabilized product, the only thing left is testing error. Odd indeed.

No kidding. I've been testing or years, so I don't think there's an error involved. But just to be sure, I repeated the tests when the numbers first started increasing; the results were the same.

 

[Texas Splash]

The only other thing we didn't mention was the R-0013 itself. But that is a stable, inert liquid that has a relatively long shelf life, so unless it was exposed to heat or sunlight, I doubt the reagent was bad.

 

[cowboycasey]

Do you need new glasses

Other than that I have no idea, is there someone else who could look at it and see?? How many times do you pour back and forth, sometimes I will do it 20 times...

 

[duraleigh]

CYA only gets in your pool if you or someone else puts it there. Since you didn't......someone else did.

If that's impossible, then your testing is at fault.

I am curious why you would test CYA (normally monthly or so) for three consecutive days when you got a steady 35 ppm the first two days.??

 

[eagle47]

The only other thing we didn't mention was the R-0013 itself. But that is a stable, inert liquid that has a relatively long shelf life, so unless it was exposed to heat or sunlight, I doubt the reagent was bad.

Yeah, just checked. The reagent has an expiration date of 07-21.

 

[eagle47]

Do you need new glasses

Other than that I have no idea, is there someone else who could look at it and see?? How many times do you pour back and forth, sometimes I will do it 20 times...

I shake for 30 seconds as per test kit instructions. And yeah, like everything else at my age, my eyes are probably starting to go.

 

[eagle47]

CYA only gets in your pool if you or someone else puts it there. Since you didn't......someone else did.

If that's impossible, then your testing is at fault.

I am curious why you would test CYA (normally monthly or so) for three consecutive days when you got a steady 35 ppm the first two days.??

Wow...monthly, really?? Maybe it's just me and wanted to stay on top of things, but I test FC, pH, and CYA daily. Overkill?

 

[YippeeSkippy]

yeah.... over kill. I'd suggest if your pool is established and stable doing the FC/CC and pH every other day or so. The TA and CH maybe every two weeks. The CYA monthly.

And of course if you've added or drained significant amounts of water or chemicals I'd do extra checks then to confirm.

Maddie

 

[Oly]

Let the water/reagent mix settle for 30 seconds after shaking and even pour it out and back in to test it again to confirm your reading.

 

[eagle47]

Let the water/reagent mix settle for 30 seconds after shaking and even pour it out and back in to test it again to confirm your reading.

OK, good suggestions. I'll give it a try.

 

[revitup]

Try new reagent. I know that it's supposed to last forever but I had the same experience. Rapid unexplained CYA increase. I got new reagent and back to normal expected numbers.

 

[cowboycasey]

I shake for 30 seconds as per test kit instructions. And yeah, like everything else at my age, my eyes are probably starting to go.

I am with you but mine took almost a year to figure it out LOL, the Doc asked me why didn't I see her 2 years ago... well ya see........

 

[eagle47]

OK, good suggestions. I'll give it a try.

Letting solution settle and retesting yielded identical 50 ppm reading. Lower than yesterday unsure, but still higher than seasonal average to date. This may be just one of those "mysteries of life" than defy explanation.

 

[eagle47]

Try new reagent. I know that it's supposed to last forever but I had the same experience. Rapid unexplained CYA increase. I got new reagent and back to normal expected numbers.

Will give it a try; guess anything is possible.