SLAM Complete - Question about TFP Recommended FC Level

[dcjbhm]

Howdy,

I have completed the SLAM and I have passed all three tests! FC was 8.2 last night and exactly the same this morning. Water is crystal clear. Yay!

The pool math calculator is telling me that recommended FC level for my pool is between 3-7. My CYA is around 40.

Last night my PH was 7.2 and my FC was at 5 when I went swimming (before adding Chlorine for the night) and my eyes have been burning since. Is that because closer to 3ppm chlorine would make for more pleasant swimming? I am trying to determine where I want to fall in the "between 3-7".

Suggestions?

Most recent test results:

FC 8.2
PH 7.4
TA 90
CYA 40

21k gallon, in-ground, vinyl liner pool; sand filter; North Florida.

 

[Oly]

Did you test combined chlorine, CC?

 

[mknauss]

Irritated eyes are from CC or pH. As Oly said, did you test CC?

You may need to raise your pH a touch. Use aeration.

 

[Richard320]

The 3-7 is the good range. 3 is the minimum. The high number is your target when you dose. Every pool is going to be different depending on sunlight and swimmer load. You'll have to figure out yours by testing and watching. If you dose to 7 and 24 hours later you're at 5, you lose 2 per day, so you want to target 5 plus maybe another .5 for safety. Then it won't drop below 3.

Burning eyes.... that varies. CC can do it. 7.2 pH might be too low for your eyes. Some people's eyes prefer a high salt level If you replaced a lot of water early on, you might have low salt level and so you get red eyes.

 

[dcjbhm]

Did you test combined chlorine, CC?

CC is 0. It must be the PH, then.

 

[dcjbhm]

The 3-7 is the good range. 3 is the minimum. The high number is your target when you dose. Every pool is going to be different depending on sunlight and swimmer load. You'll have to figure out yours by testing and watching. If you dose to 7 and 24 hours later you're at 5, you lose 2 per day, so you want to target 5 plus maybe another .5 for safety. Then it won't drop below 3.

Burning eyes.... that varies. CC can do it. 7.2 pH might be too low for your eyes. Some people's eyes prefer a high salt level If you replaced a lot of water early on, you might have low salt level and so you get red eyes.

That makes sense. Thank you!