CYA was non existent, now too high. Grrrr

Jamie A 14

Active member
Aug 11, 2015
St Johns, MI
I had zero cya a week ago, I followed pool
Math, added 60 ounces granular stabilizer via the sock method, letting pump run 24 hours, then on and off after till all was dissolved about 4 days later. Tested today and it's 70! And pool math tells me to replace 43% water. Sorry, no way....after adding water already, shocking, brushing the heck out of it. Also, ph is at 7.8. Chlorine was at 3, water is pretty clear and it's still pretty chilly here, water is cold. This is frustrating, this is our 6th year with our pool and sometimes it still feels like a crapshoot to me!


Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
Tucson, AZ
How sure are you of your pool volume?
My calculation puts it around 13,700 gallons (assuming average of 4' depth) not the 16k in your signature.

What are you testing with?
How sure are you that CYA was really 0ppm and not just something below the minimum of the test?

How many ppm of CYA were you attempting to add?

Using 13700 gallons, 60 oz would have only added 33ppm.

Are you following the process?

What is a Frog Cycler?

EDITED due to messed up numbers.


Well-known member
Mar 26, 2014
San Jose, CA
I'm sure the experts will way in shortly, but i believe that when CYA is less than 20, it will show as zero on the test. However, you still could have some there without knowing it, so it's always best to undershoot when adding CYA to be safe and not go over the desired target amount. Also, your pool volume may be smaller than you think. With the backwashing that you'll be doing with your sand filter throughout the season, you will be dumping a decent amount of water and hence your CYA will come down slowly with it.


Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
Bedford, TX

Well something is not right..

60 oz or about 4 lbs of dry stabilizer will only increase your CYA by a little less than 30 ppm...

I can only assume your original test was way off???

You can live with 70 ppm...


Jim R.