CYA Next to Non-Existent

[Swataz]

Hi folks.

I am a little baffled here as this has NEVER been an issue with my pool before, but my CYA levels are WELL below the minimum levels.

I live on Long Island, NY here in the northeast, which had a pretty wet late winter and most of the spring, so perhaps the large amount of water that was pumped to keep my pool from overflowing (mesh cover) had something to do with this issue. Am I completely off base as to the origin of the issue?

Regardless, I need to add this to allow my chlorine to stay in my pool long enough to keep algae blooms from forming.

All of my other levels are within norms, save for the chlorine levels which are linked to the massive lack of CYA, so I am assuming hitting it with 8-10 lbs for my 25,000 gallon pool will at least help.

I have another question regarding the SLAM. I believe it is best to get the pool CYA up to 30-40 BEFORE starting the SLAM. Is this the correct approach?

Thank you!

 

[mknauss]

You will want to have 30 ppm of CYA in the water when doing a SLAM. Start your SLAM when you get the CYA dissolving using the sock method.
I assume you have your own test kit. Please put the test kit brand/model number in your signature.

 

[Swataz]

You will want to have 30 ppm of CYA in the water when doing a SLAM. Start your SLAM when you get the CYA dissolving using the sock method.
I assume you have your own test kit. Please put the test kit brand/model number in your signature.

Yes, thanks, I added the kit make and model.

 

[mknauss]

The K2005 does not allow you to test FC above 5ppm. So you should add the FAS-DPD test kit.

 

[Swataz]

The K2005 does not allow you to test FC above 5ppm. So you should add the FAS-DPD test kit.

Oh, OK. Thank you!

Will this do?

Taylor K-1515-A Drop Test Kit FAS-DPD Pool Chlorine .75oz 1 Drop = .2 or .5ppm

Amazon.com : Taylor K1515A Drop Test Swimming Pool Free & Combined Chlorine FAS DPD Test Kit : Swimming Pool Maintenance Kits : Garden & Outdoor

Amazon.com : Taylor K1515A Drop Test Swimming Pool Free & Combined Chlorine FAS DPD Test Kit : Swimming Pool Maintenance Kits : Garden & Outdoor

www.amazon.com

 

[Richard320]

Hi folks.

I am a little baffled here as this has NEVER been an issue with my pool before, but my CYA levels are WELL below the minimum levels.

I live on Long Island, NY here in the northeast, which had a pretty wet late winter and most of the spring, so perhaps the large amount of water that was pumped to keep my pool from overflowing (mesh cover) had something to do with this issue. Am I completely off base as to the origin of the issue?

Not at all. You lose 3-5% CYA every month just due to normal breakdown. Rainwater and snow have no CYA in them. So you could lose so much that it won't read on the tester anymore.

Or, worst case, you got a certain soil bacteria in the pool and it turned all the CYA into ammonia. The cover may have been off long enough now that it has finished disappearing, or it may manifest itself as an unquenchable thirst for chlorine. Like, almost as fast as you can pour it thirst.

It seems you've started chlorinating already so it's too late to test now. But there's your explanation for possible causes of lost CYA.

Regardless, I need to add this to allow my chlorine to stay in my pool long enough to keep algae blooms from forming.

All of my other levels are within norms, save for the chlorine levels which are linked to the massive lack of CYA, so I am assuming hitting it with 8-10 lbs for my 25,000 gallon pool will at least help.

I have another question regarding the SLAM. I believe it is best to get the pool CYA up to 30-40 BEFORE starting the SLAM. Is this the correct approach?

Thank you!

Yep. Add enough stabilizer to raise CYA to 30 using the sock method and go. The first blast or two of bleach you can aim for 10 FC because there is no CYA. But after that consider your CYA to already be at your target and SLAM at 12 FC.

Once the SLAM is done, you can raise CYA if you want when you rebalance the rest.

And remember, we like pictures.

 

[Swataz]

So, at the risk of sounding impatient, typically how long does it take for CYA granules to dissolve using the sock method?

I have about 75% of a 4-lb container in the sock hanging from a telescopic pole right in front of a strong return jet.

Thanks.

 

[DorsalSpine]

It can take a couple of days. You can squeeze the sock periodically to speed things up.

 

[Richard320]

So, at the risk of sounding impatient, typically how long does it take for CYA granules to dissolve using the sock method?

I have about 75% of a 4-lb container in the sock hanging from a telescopic pole right in front of a strong return jet.

Thanks.

Anywhere from a few hours to a week. Depends on how thick the sock is, how strong the flow, how often you squeeze it, probably water temperature and possibly even the brand. But you don't need to wait for it to dissolve to add the bleach. If you need the pole to brush or vacuum, set the sock in the skimmer.

 

[Swataz]

Anywhere from a few hours to a week. Depends on how thick the sock is, how strong the flow, how often you squeeze it, probably water temperature and possibly even the brand. But you don't need to wait for it to dissolve to add the bleach. If you need the pole to brush or vacuum, set the sock in the skimmer.

Thanks, Richard and DorsalSpine. I read another CYA thread where you had mentioned a knee-high stocking may offer a better dissolving rate and still ensure proper delivery into the pool. Is that still sound advice?

 

[Richard320]

Thanks, Richard and DorsalSpine. I read another CYA thread where you had mentioned a knee-high stocking may offer a better dissolving rate and still ensure proper delivery into the pool. Is that still sound advice?

Yep.

See, you don't want to just dump it in the pool because it dissolves too slow and could leave freckles on the floor. And you don't want to just dump it down the skimmer to dissolve in the filter because you won;t know when it's done and you can't backwash until it's done. So the best thing is in the pool where you can see it but not loose. Hence a nylon or a sock. Sock is more durable, which may be a factor if there are kids around. Nylon allows more water through.

 

[Swataz]

Yep.

See, you don't want to just dump it in the pool because it dissolves too slow and could leave freckles on the floor. And you don't want to just dump it down the skimmer to dissolve in the filter because you won;t know when it's done and you can't backwash until it's done. So the best thing is in the pool where you can see it but not loose. Hence a nylon or a sock. Sock is more durable, which may be a factor if there are kids around. Nylon allows more water through.

Thanks, yes, I totally get the delivery being key with a pool's system. It actually is dissolving nicely in the sock at the moment in front of the return jet.

No kids, just a frustrated pool owner trying to get stuff in order before starting to entertain family and friends!

 

[Swataz]

Yep.

See, you don't want to just dump it in the pool because it dissolves too slow and could leave freckles on the floor. And you don't want to just dump it down the skimmer to dissolve in the filter because you won;t know when it's done and you can't backwash until it's done. So the best thing is in the pool where you can see it but not loose. Hence a nylon or a sock. Sock is more durable, which may be a factor if there are kids around. Nylon allows more water through.

By the way, my filter pressure spiked after the addition of the highly diluted sock of CYA this morning. Is this normal? And can I backwash it so soon? I don't want to kill my system.

 

[Richard320]

By the way, my filter pressure spiked after the addition of the highly diluted sock of CYA this morning. Is this normal? And can I backwash it so soon? I don't want to kill my system.

Yes, you can.

Your pool is What? Maybe 25 parts per million CYA right now? So you lose 1% of 25 parts per million when you backwash. Big deal. You won't even see it on the test. If you had poured it in the filter, you'd be backwashing closer to a million parts per million CYA. That's why we say use a sock. Especially when dealing witha dirty pool that is likely to need a backwash soon.