Cannot get my CYA level to increase

Jump to latest Follow Reply
I

Iwilk

0
Jun 18, 2013
65
Louisville, KY
I have added CYA twice now. A few weeks ago I added 40 ounces and a week later it tested around 20, probably under that. I added another 32 ounces about a week and a half ago and I can still see the black dot, granted it's really really light gray. We have had quite a few rain showers during all this time. Could this affect it? All my other levels look pretty good.

CC- changes daily I have to add bleach every day
FC- .5 or lower
pH- 7.8
TA- 90
CYA- low low low

Could I have something growing in my pool eating my CYA? I'm at a loss. When it's not raining it's been very sunny and humid. My pool is in direct sunlight all day and the water temp is usually 86-88 degrees.
 
How does the water look?
Are you maintaing higher FC values than you indicated?
So, what are your CCs? Are they greater than 0.5ppm?
The the CYA is getting broken down, that is usually indicated by high CC values.

With 4.5 pounds of CYA added, it should be reading up around 50ppm.
 
The water is crystal clear.
FC is always .5, it barely turns pink, 1 drop brings it back to clear
CC will go from 3 to 0 in 24 hrs. I know, I should be shooting for alot higher when adding it. I have to get more bleach.
The CYA is 99%
 
Hopefully, you got some half strength CYA and that is the cause of your situation. Do you happen to have an auto-fill on your pool though? Sometimes, the presence of an auto-fill can mask a leak that is causing your CYA to drop.
 
I hope Richard (ChemGeek) chimes in after this comment because he would definately know the answer to this but........ I have been told (and mind you have not confirmed this), that if your pH is too high when you test your CYA level, that you can get a low CYA reading. The reason for this is that if your water is too basic (high ph), the Cyanaric acid comes "out of solution" so you don't get an accurate reading. Now, this doesn't mean you have "chunks" of solid CYA floating around in your pool. Just microscopic solids that aren't reading on your test. Get your pH lower (more acidic) into the proper range and your Cyanauric Acid will go "back into solution"

Richard, if your are reading, please comment.
 

Enjoying this content?

Support TFP with a donation.

Give Support
I have been told (and mind you have not confirmed this), that if your pH is too high when you test your CYA level, that you can get a low CYA reading. The reason for this is that if your water is too basic (high ph), the Cyanaric acid comes "out of solution" so you don't get an accurate reading. Now, this doesn't mean you have "chunks" of solid CYA floating around in your pool. Just microscopic solids that aren't reading on your test. Get your pH lower (more acidic) into the proper range and your Cyanauric Acid will go "back into solution"
Click to expand...
Incorrect. pH has little to do with the CYA test.
 
Dave's right. The pH does not affect the CYA test. There is an acid buffer in the CYA reagent that forces the pH down to force full precipitation of melamine-cyanurate so any typical pool pH will be fine as a starting point. There was some question at some point with whether a high FC might affect the CYA test, but we determined it wasn't (in this thread).
 
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply