Lost a bunch of CYA and didnt realize it-trouble balancing pool

CYAnxious

Member
Jun 9, 2021
17
Western New York
Pool Size
32000
Surface
Vinyl
Chlorine
Liquid Chlorine
I've had trouble clearing up my very green pool. I had pump issues at the start of the season. I've worked on vacuuming up debris even though I couldn't see the bottom. Last season my CYA was at 110, as previous owners used pucks almost exclusively. I did replace some water throughout the season, and last I remember it was at 80.

After adding liquid chlorine yesterday, the pool continues to be cloudy but no longer green. I went to test it and was shocked to find I had .5ppm of free chlorine, 2ppm combined chlorine, ph of 8, and TA of 50. I was extremely confused and tested the CYA and it measured as less than 30. I had to fill to the very top of the tube before the dot wasn't visible anymore.

I feel like I wasted a ton of chlorine and I feel silly, but I also don't understand how I lost so much CYA. When I replaced about a 3rd of the water last year that only dropped it to 90. Since then I've replaced 2-3 inches maybe 3 or 4 times. It just seems like a drastic drop but I'm no expert.

I'm lost as to what the next steps are. Do I lower ph first? Try and raise CYA? Add more chlorine? If anyone could advise, that would be much appreciated. Thank you!
 

PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
7,250
Damascus, MD
Pool Size
29000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Jandy Aquapure 1400
I urge you to read the ABC's of pool water chemistry.

You will also need to SLAM.

There is a known CYA eating bacteria. The tell-tale sign is ammonia which you can test with a pet store ammonia test kit. As an alternative you can add chlorine and test every 15 minutes until it starts to hold.

Good luck! Please report back with updates.
 

CYAnxious

Member
Jun 9, 2021
17
Western New York
Pool Size
32000
Surface
Vinyl
Chlorine
Liquid Chlorine
don't worry that you lost chlorine and CYA. Just go forward with a SLAM to clear up your pool........your levels are just right to begin a SLAM.

Please read "Pool Care Basics" up in Pool School and then read and understand the "SLAM" article, also in Pool School
I urge you to read the ABC's of pool water chemistry.

You will also need to SLAM.

There is a known CYA eating bacteria. The tell-tale sign is ammonia which you can test with a pet store ammonia test kit. As an alternative you can add chlorine and test every 15 minutes until it starts to hold.

Good luck! Please report back with updates.
Thank you for your replies! I have read the ABCs of Pool chemistry and I was beginning the SLAM process, I just didn't expect to have such a drop in FC and such low CYA. I guess my confusion is that the CYA is outside of the recommended range. Is 20 really alright?

I added the recommended amount again last night prior to anyone's replies. Today I'm at .8 ppm FC, 12 CC, 7.4 Ph and 60 TA.
I've added the recommended amount to SLAM a little bit ago and im going to test again at 30 mins to see if I need more, assuming it's not holding due to Ammonia. Will update shortly.
 
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PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
7,250
Damascus, MD
Pool Size
29000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Jandy Aquapure 1400
Thank you for your replies! I have read the ABCs of Pool chemistry and I was beginning the SLAM process, I just didn't expect to have such a drop in FC and such low CYA. I guess my confusion is that the CYA is outside of the recommended range. Is 20 really alright?

I added the recommended amount again last night prior to anyone's replies. Today I'm at .8 ppm FC, 12 CC, 7.4 Ph and 60 TA.
I've added the recommended amount to SLAM a little bit ago and im going to test again at 30 mins to see if I need more, assuming it's not holding due to Ammonia. Will update shortly.

I don't think 12CC is possible. For now, just concentrate on getting chlorine to last longer than 15 minutes. If you do have ammonia it will take a lot of chlorine to neutralize it.
 
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CYAnxious

Member
Jun 9, 2021
17
Western New York
Pool Size
32000
Surface
Vinyl
Chlorine
Liquid Chlorine
I don't think 12CC is possible. For now, just concentrate on getting chlorine to last longer than 15 minutes. If you do have ammonia it will take a lot of chlorine to neutralize it.
Yes, 30 is a little better since 20 is sometimes hard to measure but you will be fine as long as the dot obscured when you filled the tube.

Double check that cc of 12........did you mean 1.2?
Well folks, I'm officially overtired. I don't know WHAT I did to get that cc number.
I just retested (carefully) and the chlorine seems to be holding. FC is at 11 ppm and CC is at 1 ppm
 

PoolStored

Gold Supporter
TFP Guide
Jun 24, 2021
1,673
Ashtabula, OH
Pool Size
30000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-60
I just retested (carefully) and the chlorine seems to be holding. FC is at 11 ppm and CC is at 1 ppm
We have all been there! I've redone tests a couple times when I lost count. All good.

Continue with your SLAM! You will get there!!

Where you will be --> How Clear is TFP Clear?