Major CYA loss

Jump to latest Follow Reply
M

Michipooldude

Active member
May 26, 2020
29
Michigan
Pool Size
36000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Hello all. I’m a pool noob here but eager to learn. I’ve been reading around these forums and getting familiar with my pool at my new home. We moved in about 2 years ago and continued to use the previous owners pool company for bi weekly service. The costs were astronomical so I have slowly been learning to do most things myself and finally completely took over pool maintenance myself this year.

I have been dealing with a major loss in CYA. Pool is a 36,000 gallon gunnite pool with water features and spa that overflows to pool. Algae has been present as I keep scrubbing almost daily. It’s mostly controlled now but my SWG cannot keep up and I keep having to dump chlorine in just to keep the levels up. I have been testing CYA every few weeks and it keeps dropping to 0-10 from 60 or so. My goal is to have it at 70. I believe I have probably dumped 8 gallons of CYA in this pool this year alone since early May and just measured cya today again at 0-10. I believe this is why I am losing chlorine and gaining algae and also why my swg cannot keep up.

any ideas as to why I would lose so much CYA in such short a time? The pool does have an auto fill but I can’t imagine we would be losing enough water to change the cya levels that much in such a short amount of time. I could be wrong though. Thank you for your help!
 
How are you testing your pool water chemistry? Please fill out your signature. Are you still attempting to use the Intellichem?

CYA only goes down quickly from draining pool water and adding fresh water or if the FC is left at 0 for some time and bacteria converts it to ammonia. At that point, the pool will not show any FC until the ammonia is eliminated.
 
Michipooldude said:
Hello all. I’m a pool noob here but eager to learn. I’ve been reading around these forums and getting familiar with my pool at my new home. We moved in about 2 years ago and continued to use the previous owners pool company for bi weekly service. The costs were astronomical so I have slowly been learning to do most things myself and finally completely took over pool maintenance myself this year.

I have been dealing with a major loss in CYA. Pool is a 36,000 gallon gunnite pool with water features and spa that overflows to pool. Algae has been present as I keep scrubbing almost daily. It’s mostly controlled now but my SWG cannot keep up and I keep having to dump chlorine in just to keep the levels up. I have been testing CYA every few weeks and it keeps dropping to 0-10 from 60 or so. My goal is to have it at 70. I believe I have probably dumped 8 gallons of CYA in this pool this year alone since early May and just measured cya today again at 0-10. I believe this is why I am losing chlorine and gaining algae and also why my swg cannot keep up.

any ideas as to why I would lose so much CYA in such short a time? The pool does have an auto fill but I can’t imagine we would be losing enough water to change the cya levels that much in such a short amount of time. I could be wrong though. Thank you for your help!
Click to expand...
Only thing I can think of is ammonia.

Ammonia - Further Reading

www.troublefreepool.com www.troublefreepool.com
EDIT: mknauss beat me to it
 
mknauss said:
How are you testing your pool water chemistry? Please fill out your signature. Are you still attempting to use the Intellichem?

CYA only goes down quickly from draining pool water and adding fresh water or if the FC is left at 0 for some time and bacteria converts it to ammonia. At that point, the pool will not show any FC until the ammonia is eliminated.
Click to expand...

hello I just updated my signature I believe. I do use the intellichem as well as a pHin and I have test strips from local pool store.

I just purchased an ammonia test kit from pet store and I indeed to have immonia. Unfortunately I dumped 16lbs of cya in the pool right before posting this so I’m not sure if I should proceed with the ammonia slam or wait till cya is all eaten up again. Thanks!
 
If the cya has been converted to ammonia, the bacteria is most likely dead, especially if you have added any chlorine.
So I take it you do not have any way to properly test your pool water chemistry. Without that, our help will be limited.
 
During the summer the heat depletes my CYA slowly. I have to throw in a little maybe every 1-2 months. You have something else going on.

Also you state you "dumped" 16 pounds of CYA in. CYA doesn't dissolve too easily so if you are truly just throwing in it, it might be sitting on the bottom of the pool. I put it in a skimmer sock or panty hose and let it sit in the skimmer for a while to soften up, then I hold it in front of a return jet and massage or squeeze it to dissolve it all.
 
You'll need to add chlorine until all of the ammonia is neutralized. This could take 50 gallons of bleach depending on how much ammonia you have. Add 10 gallons of bleach, test the water 15 minutes later and see if you have any chlorine reading at all. If not, test ammonia again to see that level. Repeat until your pool holds chlorine and all of the ammonia is gone.
 
Also I did want to give you guy a screenshot of my PHin readings since pool opening. This has been going on since we moved here. Concstsnrly hsving to dump chlorine in the pool. You can see it drop daily or every other day and them go back up when I dump Chlorine in……0B2C1A99-6DAE-46DB-A2DA-835477105E10.jpeg
 
PoolGate said:
You'll need to add chlorine until all of the ammonia is neutralized. This could take 50 gallons of bleach depending on how much ammonia you have. Add 10 gallons of bleach, test the water 15 minutes later and see if you have any chlorine reading at all. If not, test ammonia again to see that level. Repeat until your pool holds chlorine and all of the ammonia is gone.
Click to expand...
Thank you. I do have chlorine in the pool but it constantly drops over the span of a day or two and then I have to dump more chlorine in. I am going to attemp to follow the ammonia slam procedure they linked here earlier and report back.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Michipooldude said:
Thank you. I do have chlorine in the pool but it constantly drops over the span of a day or two and then I have to dump more chlorine in. I am going to attemp to follow the ammonia slam procedure they linked here earlier and report back.
Click to expand...
Chlorine has to be added daily it won't last 2 days unless it's a lot of fc that you shouldn't have anyway.
 
Michipooldude said:
Thank you. I do have chlorine in the pool but it constantly drops over the span of a day or two and then I have to dump more chlorine in. I am going to attemp to follow the ammonia slam procedure they linked here earlier and report back.
Click to expand...

If there is ammonia, Chlorine won't last 15 minutes. It immediately reacts with ammonia to neutralize it. Can you post a pic of your ammonia test strip or tube?
 
Michipooldude said:
Also I did want to give you guy a screenshot of my PHin readings since pool opening. This has been going on since we moved here. Concstsnrly hsving to dump chlorine in the pool. You can see it drop daily or every other day and them go back up when I dump Chlorine in……View attachment 346892
Click to expand...

When all of your ammonia has been neutralized, your water will be very acidic, below 7 for sure.
 
PoolGate said:
If there is ammonia, Chlorine won't last 15 minutes. It immediately reacts with ammonia to neutralize it. Can you post a pic of your ammonia test strip or tube?
Click to expand...
Will do later today. It is a very large pool with a low ammonia reading so I wonder if this is why it takes 2 days or so
 
Michipooldude said:
Also I did want to give you guy a screenshot of my PHin readings since pool opening. This has been going on since we moved here. Concstsnrly hsving to dump chlorine in the pool. You can see it drop daily or every other day and them go back up when I dump Chlorine in……View attachment 346892
Click to expand...
Your using PHin for all your testing?
 
TF-100 test. Did each twice

fc = 12.5
cc = 0
CH 550
TA 200
Chlorine test looked orange couldnt even match on scale
PH 7.1
CYA 35
SALT 3600
 
No ammonia.
CYA of 40.
Looks good to me. With a SWCG, I would suggest getting the CYA to 60 or 70 ppm, but that might mess up your ORP thing.
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply