CYA high SWG - How did I get here?!

greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
FC 10 (raised due to CYA..need to raise more)
CC 0
CYA 140 (ugh!)
PH 7.4
TA 80
CH 200
SALT 3800

So I had my CYA at 80 and life was good. FC started being lower than normal so the next time I tested CYA and got a 60 result I figured that explained the FC problem. I put in PoolMath that I wanted to raise CYA to 80, it said add 21 oz so I did. Tested CYA it was 100...reading on the forum I learned to dilute to get the 50% reading. Did that yesterday. The result was 70 so really 140!😭

How in the world did 21oz get me in this trouble? Even if CYA was at 80, to get to 140 PoolMath says I would need 64oz.

I moved onto a 2nd bottle of the CYA test at the same time could something be off with those (I know....I'm probably grasping).

I really don't want to drain the pool but I guess I'll have to. The hubs is going to say "you need to hire a pool person" I can feel it coming. 😝
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,125
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
All I can figure is something was off either in your CYA testing or in your PoolMath APP configuration or estimates. When I use the tool, it's telling me to increase CYA by 20 ppm in your 15K pool requires about 40 ounces of stabilizer.
 

greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
I just checked the app...it had me with an 8k gal pool. Something must have happened when I got a new phone. I was on the struggle bus trying to get logged in to my old account but finally did.

Either way it just means the stabilizer I added wouldn't have been enough but it was too much. I have a 3rd bottle of CYA tester....I'll try that one today and see what I get.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,125
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
Remember also that if you elect to manage the water with the CYA that high, which in-turn requires the elevated FC level (13 - 15 or so), that your pH testing will not be accurate. An FC over 10 effects the pH with a higher reading. It would be ideal to lower the CYA with a bit of a water exchange, but if you can't I wanted to to keep that in mind.
 

greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
I can't stand the thought of draining half the pool so good to know on the pH. I will probably drain some but half is not going to happen.

I've been having to add around 12 oz of MA a week to keep pH in check (dang SWG). Should I just keep doing that?
 

DanF

Silver Supporter
Mar 17, 2019
409
Chandler, AZ
Pool Size
12500
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
The hubs is going to say "you need to hire a pool person".
I wish I had a dollar for every time I heard that! (from my wife).
Be strong...resistance is NOT futile!
 
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reggiehammond

Gold Supporter
Oct 4, 2020
344
Fort Worth, Texas
Pool Size
30000
Surface
Plaster
Chlorine
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I can't stand the thought of draining half the pool so good to know on the pH. I will probably drain some but half is not going to happen.

I've been having to add around 12 oz of MA a week to keep pH in check (dang SWG). Should I just keep doing that?
You could wait until the normal October rains; but draining half is going to be the answer as you won’t lose CYA fast enough as the summer fades away…
 

DanF

Silver Supporter
Mar 17, 2019
409
Chandler, AZ
Pool Size
12500
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
I'm not familiar with fiberglass pools as far as how they hold up in the summer heat after being half-drained. You could go with a "simultaneous drain and fill" approach; some ideas are mentioned in this thread, and many others on the forum.

If you chose to maintain a higher FC level until the weather is more favorable, you could pick up an electronic pH tester, which are not impacted by FC levels. I have the Apera pH60 and like it a lot. I went the electronic route because I have trouble with the colors in the drop test.
 
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greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
That is due to TA in your fill water and/or aeration. The SWCG itself is not a significant factor in pH rise.
I'm so confused by that even on this forum some people say it is and some say it isn't. I should test the TA of our fill water - I've tested pH but not TA. We don't have a water feature really, just an ugly 2 inch pipe for a future waterfall but we don't turn it on much.
I'm not familiar with fiberglass pools as far as how they hold up in the summer heat after being half-drained. You could go with a "simultaneous drain and fill" approach; some ideas are mentioned in this thread, and many others on the forum.

If you chose to maintain a higher FC level until the weather is more favorable, you could pick up an electronic pH tester, which are not impacted by FC levels. I have the Apera pH60 and like it a lot. I went the electronic route because I have trouble with the colors in the drop test.
Wouldn't a simultaneous drain/refill cause me to lose some of the fresh water with the over CYA'd water? I guess if I use our submersible pump vs pool pump it wouldn't be mixing as much uh?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
43,739
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I'm so confused by that even on this forum some people say it is and some say it isn't.
Inside the SWCG, the pH is raised. When the chlorine expends itself within the pool, that process is acidic. The overall net reaction is nearly pH neutral. Aeration and elevated TA is much more of a factor for pH rise.

Many members, in areas of benign fill water (low TA, pH water), have 0 pH rise from their SWCG.
 

greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
I would still love to know how in the world I got here. I guess that is likely an unanswerable question though. The CYA I added should not have raised it this much. :(
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
43,739
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
The only way CYA gets in the pool water is by adding it. Trichlor tablets, trichlor or dichlor powder, and stabilizer all add CYA.
 

greggjess

Member
Jun 16, 2021
24
Fort Worth, TX
Yea I know - I only added 21 oz of dry stabilizer and even if my CYA had been at 80 (which it has been since my 1st add), it shouldn't have jumped to 140. I'm just frustrated...I'll get over it.
 

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