Vinyl pool..above ground cya and chlorine

rennisdime

New member
Aug 16, 2016
4
johnstown/PA
I am getting differing info everywhere. I have an AG pool with vinyl liner. Cya is at 30 using call hypo as main sanitizer.
Question is..the pool math calculator says to keep fc btw 2 and 6 at 30cya. All websites seem to recommend keeping fc btw 1 and 2.5 for vinyl liners to keep them in good shape. So what do u suggest fc should be for my situation?
Thanks
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
8,687
Eastern Ohio
First and foremost, WELCOME TO TFP!

You’ve stumbled upon the single largest difference between TFP and other sites. Other sites fail to account for how CYA and Chlorine interact with each other. Hopefully this short video will help you understand

 

rennisdime

New member
Aug 16, 2016
4
johnstown/PA
Great info! Still one question...so if u need to increase FC to compensate for CYA..will the increase in FC be harmful to the vinyl liner..since the recommendation is btw 1 and 2.5 FC for a vinyl liner? I understand u need to increase it to kill bacteria/algae. Just concerned about liner with such high levels. Or does the cya actually lower the higher levels of FC to safe levels for vinyl?
Thanks in advance
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
8,687
Eastern Ohio
@rennisdime i like the questions you’re asking!!

As mentioned above the CYA makes the chlorine less harsh thus maintaining the level on the FC/CYA Chart is totally safe for your liner. You can learn more in this post however I’ll warn you, it’s scientific stuff that I’ve never understood. It just helps backup the experience users have had over the years that recommended levels of chlorine won’t harm your liner.
 

rennisdime

New member
Aug 16, 2016
4
johnstown/PA
@rennisdime i like the questions you’re asking!!

As mentioned above the CYA makes the chlorine less harsh thus maintaining the level on the FC/CYA Chart is totally safe for your liner. You can learn more in this post however I’ll warn you, it’s scientific stuff that I’ve never understood. It just helps backup the experience users have had over the years that recommended levels of chlorine won’t harm your liner.
Thanks for info and reply!