Drop CYA

[Pepo]

Hello,

I just lower my CYA from 100 to 70 by replacing some water, I was using 10 as a target for FC with a CYA of 100.
How much wil be now my FC target with 70 CYA?
I will replace more water in few weeks to hopefully bring it to 40-50.

Thanks in advance for your help!

 

[mikech]

FC should be 8 for a non-SWG pool while yours isn't working

FC/CYA Chart

Mike

 

[Patrick_B]

Welcome to TFP Pepo,

See the link for Pool School above. In there is a handy Cya/Chlorine chart to give you the answer.

 

[Texas Splash]

Hello Pepo. Not sure I'm following your question, so let's try to confirm a couple things:
1 - The Recommended Levels chart for your pool (link below) says FC should be 5-8; that's on any given (regular) day
2 - Now if you were doing a "SLAM" (because pool is green), then we specifically match the FC to your current CYA based on the Chlorine/CYA Chart link below; for 70 the FC would be 28.

You already know your CYA is a bit high (should be 30-50 for non-working SWG), so you might have to watch your FC more closely and adjust as necessary to keep it ideally at 8, but never lower than 5.

Did that answer your question? If you need more help, please let us know.

 

[Pepo]

Thanks to all,
I will use 8 as a target for FC.