CYA - WTF?

[dovelette]

Morning all!

Opened our pool a couple weeks ago with a new liner and fresh water. Started the BBB method and had the water tested at the pool shop while we waited for our "big boy" pool test kit. Our numbers were "good enough" (I posted them here and was told it was fine) except CYA, which they tested at 20. So we added 28oz of the powdered stuff in a sock. Stuck it near the return and gave it a good squeeze once a day. It dissolved.

During this time, everything has been great pH and chlorine wise (using a basic kit), and the pool is gorgeous (something my BF insisted wouldn't happen given his problems in the past). IT's been very rainy, and with the solar cover on we've only needed to add chlorine every other day or so. Totally clear and sparkling and making me a happy camper

Got our TF-100 in the mail, just tested today, and everything is pretty stable...except after adding the CYA, and doing the CYA test, I'm registering zero. ???

Chlorine - 4
pH - 7.2
TA - 80 - 90

I do want to get the pH and TA up a bit but am mostly concerned about the CYA. I did the test twice and got the same results both times.

Am I doing the test wrong? Is it possible that the CYA went from 20 to none, because of the rain (and because the pool testing places are often off)? Not sure what to do now...considering adding liquid CYA?

 

[Richard320]

Re: CYA - ***?

Considering the tester won't read below about 30 and the original test was done by a pool store...I don't think you have a whole lot to worry about. Sounds like nothing worse than low CYA. If rain water's been diluting the pool, that will also account for things. Your average depth is about 60", so even 6 inches of rain will affect things by 10%.

Review the CYA test procedures, and repeat the test. Don't neglect to pour the solution back and take several readings. Then if you're still convinced the CYA is low, add more. But go easy - what looks like zero may be 20.

 

[woodyp]

Re: CYA - ***?

It's much more likely that your pool store test of 20 was erroneous in the first place! Wait a couple more days, test again, and then adjust CYA again if needed. You wanna be wrong on the LOW side.

 

[vanessadickson]

Re: CYA - ***?

Let me throw in my two cents as a novice tester and having made a common mistake--is it possible you didnt shake up the CYA for a full 30 seconds before pouring into the testing thingy? Makes a whale of a difference.
--Your friend "Been There, Done That"

 

[dovelette]

Re: CYA - ***?

Let me throw in my two cents as a novice tester and having made a common mistake--is it possible you didnt shake up the CYA for a full 30 seconds before pouring into the testing thingy? Makes a whale of a difference.
--Your friend "Been There, Done That"

Ummm...Yes it's entirely possible LOL. I shook it for about 5 seconds, let it sit for 30 seconds or more, then shook again. I thought that was what I was supposed to do. Sounds like I'll try it another way when we get back from garage sale-ing. And if it's still low, I'll wait a couple days, test again, and then add more CYA in VEEERY slowly, like to raise it 10ppm a pop.

Thanks guys! I'm so happy I bit the bullet and went the BBB route and have this forum instead of going with a low chlorine system. I have to go out daily to my garden to check on my edible friends progress, so adding a quick stop to check levels is cake (I actually timed it on lunch one day - it takes me 14 minutes to put on a bikini, take off the solar cover, skim the pool, test for pH and chlorine, and swim 200m. As someone who telecommutes, I can't think of a better way to spend my breaks).

 

[Richard320]

Re: CYA - ***?

Let me throw in my two cents as a novice tester and having made a common mistake--is it possible you didnt shake up the CYA for a full 30 seconds before pouring into the testing thingy? Makes a whale of a difference.
--Your friend "Been There, Done That"

Ummm...Yes it's entirely possible LOL. I shook it for about 5 seconds, let it sit for 30 seconds or more, then shook again. I thought that was what I was supposed to do. Sounds like I'll try it another way when we get back from garage sale-ing. And if it's still low, I'll wait a couple days, test again, and then add more CYA in VEEERY slowly, like to raise it 10ppm a pop.

Thanks guys! I'm so happy I bit the bullet and went the BBB route and have this forum instead of going with a low chlorine system. I have to go out daily to my garden to check on my edible friends progress, so adding a quick stop to check levels is cake (I actually timed it on lunch one day - it takes me 14 minutes to put on a bikini, take off the solar cover, skim the pool, test for pH and chlorine, and swim 200m. As someone who telecommutes, I can't think of a better way to spend my breaks).

 

[dovelette]

Re: CYA - ***?

LOL