Chlorine Loss Trying to Prevent a Problem

[Smokenjoe420]

A few days ago I decided to up my calcium count. Everything I saw said not to add chlorine for 24 hours after raising calcium. When time came to add chlorine again I was at zero! I brought my chlorine back to 5ppm. That was Wednesday night. Thursday evening when I tested to add more chlorine my ppm was 1. Prior to adding calcium and my FC dropping to 0, my FC levels would be 5ppm and by time to add more would drop to 3. Last night I did the OCLT and only lost 1ppm. So I believe I'm straight here, just a little concerned. Should I just keep an eye on it and roll on? My water is gorgeous with no signs of issues anywhere. I am about to bump CYA from 35 to 50 though.

FC currently 5
TA 90
CH now 150
PH 7.5
CYA 35
Borates 50

 

[ajw22]

We have seen the addition of calcium cause FC go to 0. We don’t have an explanation for it.

Just raise your FC back up and move on.

Calcium Hardness - Further Reading

www.troublefreepool.com

 

[Newdude]

We have seen several reports of Calcium adds depleting FC. We can't replicate then so we assume it's from the impurities in certain brands.

On a side note, you are flirting with minimum FC and while it hasn't bit you yet, it's only a matter of time. Raise your target to end up at 5 or more after the daily loss, to allow some wiggle room for whatever the universe throws at your pool. Like an unexpected FC drop from CH, or a particularly high UV day, or a storm, or 100 other oopsies.

 

[Smokenjoe420]

We have seen several reports of Calcium adds depleting FC. We can't replicate then so we assume it's from the impurities in certain brands.

On a side note, you are flirting with minimum FC and while it hasn't bit you yet, it's only a matter of time. Raise your target to end up at 5 or more after the daily loss, to allow some wiggle room for whatever the universe throws at your pool. Like an unexpected FC drop from CH, or a particularly high UV day, or a storm, or 100 other oopsies.

I appreciate your feedback. I was hoping my FC levels prior to adding calcium was good. Reading I need to up it is a little disheartening. I'm already experiencing dry skin especially my face and hands after swimming. Wouldn't raising my FC levels make that experience worse? I swim a lot. Every morning and every evening I'm in the pool. So you're saying raising to 5 and ending at 3 is not good for FC?

 

[Newdude]

Reading I need to up it is a little disheartening.

Nope. No worries there.

Wouldn't raising my FC levels make that experience worse? I swim a lot.

Up to SLAM is less harsh than your municipal water with 0CYA and up to 4 FC. Come swim in my pool running hot at 10 to 14 FC. It's less harsh than taking a shower/bath.

So you're saying raising to 5 and ending at 3 is not good for FC?

Correct. It's dancing the line of not being sanitary. Ironically, if the swimmers itch bacteria festers, being low will give you irritations or rashes.

 

[Smokenjoe420]

Nope. No worries there.

Up to SLAM is less harsh than your municipal water with 0CYA and up to 4 FC. Come swim in my pool running hot at 10 to 14 FC. It's less harsh than taking a shower/bath.

Correct. It's dancing the line of not being sanitary. Ironically, if the swimmers itch bacteria festers, being low will give you irritations or rashes.

Little update to your response and my original post. So for 2 nights I've bumped FC to 7. I lose 1ppm overnight which according to OCLT I'm fine. Then throughout the day I lose another 3ppm. So I end my cycle at 3ppm. Our weather right now is in the 90s with 80+ percent humidity. My pool is in direct sunlight all day. I did bump my CYA to 40 and I'm waiting for more to bump it to 50. What do you recommend I bring my FC to at night? I'd like to quit having to add so much chlorine every evening. I will say it wasn't doing this until it got this hot out.

 

[Newdude]

I will say it wasn't doing this until it got this hot out.

It's the peak season for all of us. Yours is harsher than mine and someone down in TX is laughing at both of us. We will all be adding our highest amount of FC to combat the daily loss.

What do you recommend I bring my FC to at night?

9 - 4 = 5. (Allowing some wiggle room for FC loss events to happen).

Once you raise to 50, I'd do
10-4 = 6.

I'd like to quit having to add so much chlorine every evening

Consider a SWG. I cannot promote the convenience of one enough. It's considerably cheaper in the long run, and no jug lugging. Most are even more, but my pool is huge so my SWG only saves me lugging 1005 jugs. At $5.67 each, plus tax that's $6199.80 in liquid chlorine if I did it the hard way.