Why CYA of 60ppm "Not Recommended" for SWG pools?

goody222 · Apr 17, 2019

On the Chlorine / CYA chart for salt water pools, a CYA of 60 is not recommended. The last couple of weeks my FC has been 8ppm with CYA 60 (had to order more CYA). Adding stabilizer today, but just curious why this is not recommended as long as I'm maintaining FC well over the minimum. Thanks!

Texas Splash · Apr 17, 2019

goody222 said:
just curious why this is not recommended as long as I'm maintaining FC well over the minimum.

The FC/CYA Levels addresses levels of a typical swimming season. Since we just entered spring and many pools are either still opening or still have cold water, they can get-by with a lower CYA. That's fine. But once swimming season gets here and the FC demand increases for your pool, you'll want to be in that TFP recommended range. Have a nice day.

goody222 · Apr 17, 2019

oh yes, I understand that. Just wondering if there was a health / equipment damage issue with those levels.
Plus, I've overshoot a couple of CYA adds last year trying to stay high in band and now prefer to let it drop low out of band than go too high.

Jimrahbe · Apr 17, 2019

222,

We recommend 70 to 80 so that the SWCG does not have to work as hard in the middle of the summer.. You can run your CYA at whatever level you like below 70, it will just mean running the SWCG harder to keep the FC up to your target... CYA being a little too high or a little too low will not hurt anything..

Jim R.

goody222 · Apr 17, 2019

ok, great! So its an efficiency issue. I'd rather work my SWG a little harder than go over 90 ppm again (had to SLAM twice last year and that might be the cause - I'm also now keeping FC above target level)

Jimrahbe · Apr 17, 2019

Mark,

Just to be clear... you do not have to run above your target level to prevent algae, but it does allow you to test less often and not run the risk of having your FC drop below the minimum. I also run my FC on the hot side for the same reason..

I have three pools and since I started using the TFP process, about six years ago, have never had algae or the need to SLAM. If you had to SLAM twice last year, then something is not right... It could be that you have never really gotten rid of all the algae.. Maybe hiding behind the light or under a ladder or???

Something to look for this year if it ever comes back..

Thanks,

Jim R.

goody222 · Apr 17, 2019

Thanks Jim! So last year was my first full year with a pool and there were a few times my FC dropped to min levels (getting a feel for salt cell %). I want to maintain higher FC just like you said - so if I miss testing here or there, have full sun for 2 weeks, etc, that I don't drop low out of band.

I actually made myself a note to take the cover off my Hayward Colorlogic lights to check for any algae when it is warm enough to swim in, just to be sure. I've also learned that I should be brushing the sides of the pool. I didn't brush at all last year. I already started brushing and plan on doing it once a week for the entire season.

ajw22 · Apr 17, 2019

Chesapeake, Virginia does not get the sun intensity that TX and AZ do. The TFP guidelines have to work over a wide range of environments. CYA 60 will work fine by you with the correct SWG FC settings. I run my CYA in the 60-70 range.

CYA 60 will not work as well down South.