How critical is having high CYA in a SWG pool?

[Goshdurnit]

We've got a 4th of July party coming up, and it'll be the first time we've used our newly replastered pool.
Levels are looking pretty good- for a 14k gallon pebbletec pool, IC40 salt cell running at like ~20% right now with ~3600 PPM salt.
FC is about 3 PPM-ish, CYA is about 40. pH is a constant battle to keep down, but I'm muriatic-acid-ing every other day.

My question- how important is it to raise the CYA to 70+ immediately? Should I work hard to bump that in the next couple days before the party?
My previous pool guy suggested that I should wait til winter to get the CYA way high, because if I want to use pucks in the winter when the SWG won't work because it's too cold, it'll go up fast then anyway. ( I do realize pucks are a no-no around here, but oh-so-convenient)

At ~40 CYA, my SWG should have no problem maintaining about 3 PPM FC, which is 7.5% of 40. I'm just trying to understand how important it is to go by the TFP CYA recommendations, or if this is one area where I can wing it a bit.
I'd like to keep my chlorine levels low-ish, so as not to irritate skin if possible... or is that a myth?

 

[ajw22]

If your SWG can maintain your TFP target FC level with CYA 40 then you are good. CYA 70 will require less daily FC and a lower generation % and a longer life to your cell. In some high sun locations higher CYA becomes mandatory.

I'd like to keep my chlorine levels low-ish, so as not to irritate skin if possible... or is that a myth?

You need to learn how CYA buffers chlorine and the active chlorine (HOCL) with TFP recommendations is way way less then 3 ppm of FC with no CYA.

Read CYA Chlorine Relationship - Further Reading and then let’s discuss any questions you have.

I would not wait till winter to raise your CYA to at least 60. But you can do it after your pool party.

CYA - Further Reading

www.troublefreepool.com

 

[duraleigh]

how important is it to raise the CYA to 70+ immediately?

Not at all!. Leave your CYA at 40 if you wish. That said, your SWG may not keep up well as the summer heat continues and going to CYA 70 as TFP suggests, will help your SWG do it's job.

 

[ajw22]

With CYA 40 your FC target is 3-7. I would not run FC at the low end 3, especially with a pool party.

I would increase FC to the high end of the range, 6-7.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

 

[Oly]

Stay in well into your target zone with your FC before and after your party, FC/CYA Levels
I would suggest getting a couple of gallons of liquid chlorine (no additives) on hand now and be proactive with your FC levels with frequent testing. Have a fun time with your clean pool.

 

[jgofnj]

3 PPM is way to low for my comfort zone, if it were me, I would bump up the SWG to 40% at least until the party is over. Someone on this board once describe the FC range as a cliff, do you want to me walking on the very edge of a cliff? Give yourself a buffer and raise you output.

 

[Donald55]

Your pool sounds ready for the 4th of July party! It's good to raise CYA levels to 70+ for better chlorine stability, but you can do it gradually after the party. Low chlorine levels are better for skin comfort. Enjoy your party and have a great time

 

[Bperry]

Your pool sounds ready for the 4th of July party! It's good to raise CYA levels to 70+ for better chlorine stability, but you can do it gradually after the party. Low chlorine levels are better for skin comfort. Enjoy your party and have a great time

want to clarify this comment about “low chlorine levels” since its not a precise enough statement to be clear that the comfort level of chlorine is dependent on the CYA level.

A free chlorine level of 1ppm without any CYA is way more harsh than the same 1ppm FC with 30ppm CYA. But that same 1ppm chlorine in a high CYA water is inviting algae and bacteria that can cause skin irritation. So blanket statement of low chlorine levels being better for comfort needs some qualifications added to be clear to newer users viewing this thread.

 

[farmy87]

( I do realize pucks are a no-no around here, but oh-so-convenient)

They aren't really a "no-no"; they are a perfectly acceptable way to add FC if you realize they are also going to raise your CYA. Some people (myself included) start the CYA on the low end at the beginning of the year so that we can use pucks on short vacations to help maintain FC and have some wiggle room for the CYA to rise in the process.

 

[pjt]

I'd like to keep my chlorine levels low-ish

That's a recipe for major problems.

Keep your FC above the target FC for your CYA level at all times, and you'll enjoy safe, sanitary water. It's safe to swim up to SLAM level FC. There's no downside to keeping your FC a little high. There's significant risk flirting with low FC levels.

 

[jgofnj]

Low chlorine levels are better for skin comfort.

Disagree. Keep you FC on the high end of the range. No one will ever know.

 

[proavia]

FC/CYA Levels