CYA jumped to 100 with pool-math calculation

southflorida427

Well-known member
Apr 27, 2017
88
Miami FL
Scratching my head, usually the math works great.

I added 3lbs dry CYA for my 13K gallon pool that measured 40ish CYA to try to take it to SWG recommended level of 70.

I also added salt, calcium, acid, recently. Reasons I’m our of wack: dear kids left the water hose Inside pool overnight and I found myself with a diluted infinity patio/pool in the morning...

Today tested with both taylor and pentair (this one new, arrived today) test kits and I’m around 100.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
29,694
Laughlin, NV
Well, either the first CYA test was incorrect, you added more than 3 lbs of CYA, your pool volume is much less than you thought, or the last CYA test is incorrect. Or the pool is just not mixed up well. Did you run the pump a full 24 hours after the CYA was dissolved completely?
 
  • Like
Reactions: southflorida427

southflorida427

Well-known member
Apr 27, 2017
88
Miami FL
Yup, it’s been running for 24 hours already. I do notice the filter went up in pressure a bit.

I think today’ test are OK, I bought 5 lbs acid and still have 2lbs in the bag. Pool size I’ve been using for years to calcule chemical additions.

The only part I guess I cannot corroborate is the 40ish test.
Next time I’ll add in smaller batches.

Anything else that could be going on?
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
23,612
San Dimas, CA (LA County)
Unless you have algae, or suspect it, you can just run a higher FC.

At least until you figure this out. Maybe consider CYA to be 100 for now, run the higher FC level for a few days, and then recheck it and move forward from there. I could understand wanting to postpone water replacement until the next billing cycle since you've already added a whole bunch.

My guess is that the water wasn't mixed well enough before you ran the first test.
 
  • Like
Reactions: southflorida427