CYA Testing Error 🤔

[dash]

Hello,
This morning I tested the CYA level in my pool, and the number was ZERO. Last week, I'd put 2 cups of stabilizer in a sock for dispersion, and so I'm trying to determine if I really just need more stabilizer, or could there be an error with chemical R-0013 that I used in my CYA test. My test kit chemicals are over 2 years old, and I wanted to get advice about whether the R-0013 additive for the CYA viewing test could be the culprit, or does my pool really need A LOT more stabilizer?
Thanks!

 

[proavia]

Do you store your test kit inside the house? The R-0013 is probably one of the most stable reagents in the kit. That being said, if your reagents "are over 2 years old", you should probably replace them all.

 

[dash]

I do keep my test kit inside, and you're right about buying new reagents and chemicals.

 

[proavia]

Well, it's going to hit 100 by next Friday here in the valley. Having fresh, reliable reagents will help keep your pool trouble free for the season. While you are waiting for your reagent refill kit, just keep the FC level up.

What was your CYA level the last time you checked - before this current reading? I would use that CYA level to dose FC, based on the FC/CYA Levels, until you get your refills.

I see you are sharing your PoolMath logs, but they are empty.

 

[EAnton]

My kit stops at 30, it doesn't go down to zero. Is it really zero or just below 30?

I added about a pound this spring and still couldn't get a reading above 30.

 

[dash]

My kit stops at 30, it doesn't go down to zero. Is it really zero or just below 30?

I added about a pound this spring and still couldn't get a reading above 30.

Well, I filled up the CYA viewing tube to the top, and could see the black dot at the bottom. It was crystal clear.
I just ordered new reagents for my test kit, so I'll test again when it arrives.
Currently, I added a pound of stabilizer to the pool using the sock method.

 

[mknauss]

A pound of dry stabilizer added to a 10 K pool is 12 ppm. That would not even make the CYA test cloudy.

As Gene asked, what was the CYA the last time you tested it (late last year).

 

[dash]

A pound of dry stabilizer added to a 10 K pool is 12 ppm. That would not even make the CYA test cloudy.

As Gene asked, what was the CYA the last time you tested it (late last year).

I keep a notebook with all my test numbers, and at the end of last summer (Sept 27), the CYA tested at about 45.
It sounds like I just need a lot more stabilizer.

Would I only lose stabilizer through back washing?

 

[mknauss]

Your CYA could have degraded some over the winter. Backwashing is the only way you can physically remove it (or draining your pool). Did you maintain the FC over the winter?
It would be unusual for you to have zero CYA in the pool now with out a full drain and refill.

 

[dash]

Yes, that's my main question about having such low CYA.
I'll test it again with the new reagents when it arrives, but I've only done regular backwashes, I haven't drained it, but I seem to always be low on stabilizer for some reason.

 

[mknauss]

CYA does degrade in our high UV climate. Also high water temperatures degrade it. So it is best to test the CYA level monthly starting in May through September. I then test it again in November or December and again in March.