What if CYA is 53ish?

[psbailey]

I was looking at Ben's chart and I perceived a gap.

The chart tells you the FC range if your CYA is b/w 30 and 50. The chart then gives FC recommendations for CYA levels b/w 60 and 80.

What if your CYA is b/w 50 and 60, as mine is about 53 (its closer to 50 than 60)? Do you round down (or up) to the closest level?

Maybe I'm reading too much into the chart, as well.

Thanks,

Paul

[CarlD]

Live in the overlap!

30-50 CYA: 3-6ppm FC
60-90 CYA: 5-10 ppm FC

You'd want to be in the 5-8 range--after all, it's a Best GUESS table!

[waterbear]

How did you get a reading of 53? The CYA test does not have that much precision! Call it 50! Someone else might get a different reading because the test is subjective!

[psbailey]

Oh, yeah. 53 is a total SWAG. The water line was closer to 50 than 60, that's all.

I completely agree that the test is very subjective. It depends upon the tester's eye sight, the current conditions (cloudy, sunny, etc.) and on and on and on. I wish it weren't so.

Thanks for the reply!

Paul

[CarlD]

Paul:
Evan didn't tell you anything that contradicts my advice. That's why there's overlap.

I look at the CYA range, and the matching residual chlorine range, and try to match my residual to whatever end of the CYA range I'm at. So if 30-50 is 3 to 6, I prefer 3 for 30, 4.5 for 40, and 6 for 50. It's not hard and fast, probably isn't even necessary, but it works for me. Either way, you're at the high end of the 30-50 and the low end of 60-90. So use the residual levels for those ends of each.

Just don't get confused by it. It just SOUNDS contradictory.

[waterbear]

Carl hit it right on the head again, as usual!

[michladny]

If you get LOTS of rain (in the last two weeks I have had to get rid of approx 4 inches of water from my AG pool ---not to mention the little refills I needed to keep my water levels up after kids in there and the heat) should I add more stabilizer???? Cause of all of the rain do I have to shock my pool water? It is clear and all of my levels are fine

I tested my CYA and it went down from 60-ish to 40-ish(now).... I have a WHOLE FREE HUGE bucket of trichlor tabs so I was thinking if using them now that my CYA is lower (as I know they add it to the water). Does anyone know how much CYA the tabs will add or how often I should check the CYA?????

Thanks

Michelle

[waterbear]

IF you are planning on letting the water evaporate I wouldn't add any more becuase it will concentrate as it evaporates. If you drain some of the water out then you might want to consider it if it made your stabilizer go below 30 ppm. Since you drained some water you have diluted the CYA however a staibilizer reading of "40ish" is ,IMHO, perfect!

[psbailey]

Thanks, Carl for the advice on my "chlorine range." Its at 8 right now and I'm going to let it drift to 5 before I add more bleach.

The pool looks great thanks to the advice from you, Evan, Watermom and all the other people willing to share their knowledge. This is a great forum because of folks like you.

Warmest Regards,

Paul

[waterbear]

If anyone even suggests a group hug I'm outta here!

seriously, this is what the forum is all about and we all should give Ben a big THANKS for putting it together for us!