Here's one for you...cya disappeared.

[howardpassman]

Hi,

We had 5 inches of rain the other day and my pool was flooded with water that came from my neighbors yard. I balanced it the next day and noticed the chlorine for the next few days was disappearing quickly. I also noticed my cya was dropping. After 4 days it has dropped from 40 to 10 and that includes the fact I added 12 oz after the first drop from 40 to 35. I thought nothing removed cya, but something that washed out of my neighbors yard certainly did. I checked it three times today even opening a new bottle of Taylor's cyanuric acid. I have an 18,000 gallon concrete pool and my numbers tonight were 85.1 degrees, 2.4 FC,.3 CC, 7.56 pH, 92 TA, 240 Calc and of course cya of around 10. Too low to measure, but there is some cloudiness to the test sample.

I'm still bringing the Calc up a little and may or may not bring up the TA a hair later. Any ideas where the cya went or what could have washed out of my neighbors yard to get rid of it.

Also, right after the storm I added a does of algacide as a precaution because it's was time to add some.

Thanks,

Howard

P.S. I use chlorox bleach, baking soda, muriatic acid, etc.. to maintain my pool.

 

[borjis]

Highly likely the neighbor flooding mixed in enough to dillute it big time.

Though there has been quite a few mystery cya level drops this season.

Mine went from 50 to 20 over 2 months (May/June) with 0.0 water exchange.

But my CH level stayed exactly in the same place. Something ate my cya.

 

[JamesW]

Possibly bacteria from the soil. Certain bacteria can eat cya. Monitor fc and cc carefully.

 

[pooldv]

When FC drops below minimum it is possible for bacteria to grow and consume your CYA.

 

[howardpassman]

Thanks guys. I am checking FC and CC every day. I'll stay on top of it.

Howard

 

[max2k]

...P.S. I use chlorox bleach, baking soda, muriatic acid, etc.. to maintain my pool.

That last part is bothersome- you really don't need anything else. Please do not use algaecides or you'll be draining your water later. Your FC is dangerously low.

 

[Cinic]

I lost CYA this year as well. Never had an algae bloom and only very briefly (maybe a few hours) got below my min FC levels by 1 ppm.

TA and CH levels compared to fill water didn't change enough to blame a leak and I passed the bucket test also. The loss did coincide with some excessive bird 'activity' in and around the pool. At this point my theory is that the birds introduced some bacteria that wasn't killed before it consumed quite a bit of my CYA.

I replenished the CYA and have been back to normal since.

 

[max2k]

that bacteria needs to be segregated, cultured and sold at TFTestkits along with jugs of bleach to kill it after. Wonder what it converts CYA to after eating it?

 

[pooldv]

Ain't that thread truth!

It is a nitrification process. First it converts to ammonia, then nitrite then nitrate.

 

[JoyfulNoise]

... Wonder what it converts CYA to after eating it?

As always, chem geek had something to say about that ....

Degradation of Cyanuric Acid (CYA))

 

[max2k]

Ain't that thread truth!

It is a nitrification process. First it converts to ammonia, then nitrite then nitrate.

sounds suitable. We can even call it CYA Down or C-Gone or any other Baloney Sandwich names marketing loves What kind of bacteria is that? I wonder if the cure is not worse than the original problem ...

 

[domct203]

Hi,

We had 5 inches of rain the other day and my pool was flooded with water that came from my neighbors yard. I balanced it the next day and noticed the chlorine for the next few days was disappearing quickly. I also noticed my cya was dropping. After 4 days it has dropped from 40 to 10 and that includes the fact I added 12 oz after the first drop from 40 to 35. I thought nothing removed cya, but something that washed out of my neighbors yard certainly did. I checked it three times today even opening a new bottle of Taylor's cyanuric acid. I have an 18,000 gallon concrete pool and my numbers tonight were 85.1 degrees, 2.4 FC,.3 CC, 7.56 pH, 92 TA, 240 Calc and of course cya of around 10. Too low to measure, but there is some cloudiness to the test sample.

I'm still bringing the Calc up a little and may or may not bring up the TA a hair later. Any ideas where the cya went or what could have washed out of my neighbors yard to get rid of it.

Also, right after the storm I added a does of algacide as a precaution because it's was time to add some.

Thanks,

Howard

P.S. I use chlorox bleach, baking soda, muriatic acid, etc.. to maintain my pool.

Welcome.

How are you getting those test results (.3 CC, 7.56 pH, 92 TA)? With the k2006, the finest resolution of the chlorine testing is 0.2ppm, the pH test is by two-tenths (7.2, 7.4, 7.6 etc) and with TA, one drop = 10ppm. Are those pool $tore results?

I wouldn't bother with adjusting TA if the pH is stable.

There is no need for algaecide in a properly sanitized pool.

I see you have a 'mineral cartridge' listed in your signature. Are you aware that the mineral cartridge, along with most algaecides are adding copper to your water? These metals do not dissipate on their own and will continue to accumulate. Copper is known to stain pool surfaces and turn blonde hair green.

Dom

 

[pooldv]

I believe it is nitrosomanoas for the ammonia conversing and nitrobacter for the nitrate conversion, but I didn't look it up to verify. It is likely that is what Bioactive is trying to culture but it is too unstable and/or unpredictable.

 

[borjis]

sounds suitable. We can even call it CYA Down or C-Gone or any other Baloney Sandwich names marketing loves

LOL!!!

In my case, I theorize there is "something" in the pollen nodules my neighbors red pine drops in MASSIVE quantities in my pool.

only additive I can come up with to explain it.

 

[max2k]

LOL!!!

In my case, I theorize there is "something" in the pollen nodules my neighbors red pine drops in MASSIVE quantities in my pool.

only additive I can come up with to explain it.

going full organic someone could make floating bird feeder and then enjoy falling CYA. Then you'd need to get cats to get rid of birds - full food chain

 

[Mamiamjo]

Hi,

We had 5 inches of rain the other day and my pool was flooded with water that came from my neighbors yard. I balanced it the next day and noticed the chlorine for the next few days was disappearing quickly. I also noticed my cya was dropping. After 4 days it has dropped from 40 to 10 and that includes the fact I added 12 oz after the first drop from 40 to 35. I thought nothing removed cya, but something that washed out of my neighbors yard certainly did. I checked it three times today even opening a new bottle of Taylor's cyanuric acid. I have an 18,000 gallon concrete pool and my numbers tonight were 85.1 degrees, 2.4 FC,.3 CC, 7.56 pH, 92 TA, 240 Calc and of course cya of around 10. Too low to measure, but there is some cloudiness to the test sample.

I'm still bringing the Calc up a little and may or may not bring up the TA a hair later. Any ideas where the cya went or what could have washed out of my neighbors yard to get rid of it.

Also, right after the storm I added a does of algacide as a precaution because it's was time to add some.

Thanks,

Howard

P.S. I use chlorox bleach, baking soda, muriatic acid, etc.. to maintain my pool.

I've had similar drops twice this year already. In May after torrential rains (est 24") my CYA went down to about 20 (from 90) and again last month, after an accidental water replacement (don't ask), my CYA went from 70 down to less than 20 (I'm guessing about 10). FC was down to about 2PPM. Each time I had to add CYA to bring it up to a more amount.

 

[doncaruana]

As always, chem geek had something to say about that ....

Degradation of Cyanuric Acid (CYA))

Admins - can we put Chem Geek's post there in Pool School?? It at least ought to be a sticky some where...

 

[pooldv]

Noted, we'll review it. Thanks.

 

[max2k]

Noted, we'll review it. Thanks.

just make sure it's in more 'advanced' section of it- new members coming here are often have their head spinning of all new info they need to consume in very short time while being pressed by SO for results. I think the simpler the initial steps the better. CYA degradation is definitely not one of those 'introduction' topics IMO.

 

[Cedarpool]

As always, chem geek had something to say about that ....

Degradation of Cyanuric Acid (CYA))

For what it's worth, I have found that during the strong sun in central Texas summers in an unshaded pool I lose about 10 PPM CYA per month with no water removal (just filling due to evaporation and minor splash out). SWG that I run at TFP recommendations of 80 CYA and 4-5 FC (Thank you TFP as I have found this is absolutely critical and no one else tells you this!). Anyway this fits nicely with chem geek's last paragraph about sunlight degradation. That along with high water temperature (88-90) and the superchlorination that occurs within the cell (both of which are also discussed in article as CYA degraders) I think establishes that it is normal to lose quite a bit of CYA during summer, especially with a SWG.