CYA Adjustment Necessary..??

angelleye

Active member
Feb 28, 2022
36
Milton, FL
Pool Size
15400
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
I'm reading through the Water Balance for SWGs article and it has this statement:

Second adjust CYA to between 70 and 80. The biggest mistake that many SWG owners make is NOT having enough CYA in the water! This can create a lot of problems like high acid demand, algae outbreaks, cloudy water, or early cell failure.

We have been battling high pH and I've been using a lot of acid for that, but they're saying it's just because it's fresh plasture (build completed about 2 months ago).

Basic test strips are showing me around I'm at ~40. The pool store test is telling me I'm at ~55 and no adjustments are necessary.

I now have a TF-Pro Salt test kit, and I'm new with it, but running the CYA test I am filling the entire tube but I can still see the black dot. Maybe I'm not in the best lighting for it..??

It seems that in each of these cases I would need to add some sanitizer to get up to that 70-80 range recommended here.

I have some InTheSwim Stablizer on hand, which I'm hoping is okay to use..?? I believe it is considered Dry Stablizer in the PoolMath app, is that right?

If I enter the current level at 40 it's telling me I should add 4 lbs, 8.0oz. Should I run with that or what would you all recommend based on this info?

Any information on this would be greatly appreciated. Thanks!

EDIT: Additional note, based on what I'm seeing with this TF-Pro test kit (and strips seem to match) I am also low on TA at ~40 and CH at ~200. Again, store hasn't said any adjustments necessary on those. They just keep giving me more muriatic acid to bring the pH down.
 
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We have been battling high pH
What is your pH?

Basic test strips
This is a poor way to test. Don't use them.

The pool store test
This is also a poor way to test. Don't use them.

I now have a TF-Pro Salt test kit
This is an excellent test kit. Use it exclusively.

running the CYA test I am filling the entire tube but I can still see the black dot.
If you're performing the test correctly and get that result, you have little to no CYA in your water.

I have some InTheSwim Stablizer on hand, which I'm hoping is okay to use..?? I believe it is considered Dry Stablizer in the PoolMath app, is that right?
Yes, that's perfect to use. Yes, that's Dry Stabilizer in PoolMath.

If I enter the current level at 40 it's telling me I should add 4 lbs, 8.0oz. Should I run with that or what would you all recommend based on this info?
Slowly approach your CYA target. It's easy to add CYA, and draining is the only practical way of lowering it. I would add enough CYA to bring it up to 40 and retest.

I am also low on TA at ~40 and CH at ~200.
Can you post a full list of test results from your TF-Pro?

FC
CC
pH
TA
CH
CYA
Salt
Temp
 
Can you post a full list of test results from your TF-Pro?

I was going to do my weekly maintenance today, including all the testing with this kit. It's been raining, though, and it looks like it could be over the next couple of days.

I did do a quick Cl Br pH test and this is what it's looking like right now after the rain today:

cl-br-ch.png

I don't even see a difference on the yellow side between the 5/10 and 3/6 box colors. On both sides, though, I seem to be above max.

This is after rain today and after putting in a gallon of muriatic acid 3 days ago.

When it gets up here they give me a bottle of acid, I drop it in, later that day it'll be down in the low 7 or even 6.8. Next day it'll be around the perfect area. Then a day or two after that it's high again, even after rain (which if I understand correctly should naturally lower pH, or is it opposite?)

Should I go ahead with all the other tests even though it's raining?

EDIT: The only thing I have on hand to reduce pH right now is granular "pH Reducer" from InTheSwim. I purchased it before I read that I shouldn't use that with a SWG. I haven't put any of it in.

With high pH should I go ahead and put some in, or should I wait until I can get some muriatic acid? And shouldn't I get a handle on CYA and TA before fighting pH?

EDIT 2: The test I did yesterday with the kit gave me the following results:

FC - 5.0
pH - 8+ (it wasn't as dark as it is today)
TA - 40
CH - 200 (seems too low)
CYA - 40 (seems too low)
SALT - 3200
Temp - 83

I was not tracking CC in PoolMath so I don't have that one, but I just enabled it, so I'll be logging it going forward.
 
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It rained more today, and then I ran some more tests this afternoon. I took a sample from the pool, and then I ran tests with my test kit as well as took it to the pool shop to see what they come up with.

TestTF-Pro ResultShop Result
FC2.53.2
CC0.5-
pH8.58.4
TA5080
CH200200
CYA3055
SALT30002900

I put 1 gal of 31.45% (20° Be) Muriatic Acid in today.

The shop is telling me that 200 is within their recommended range for CH, but PoolMath is telling me I should be at 250 minimum.

They are also telling me I'm fine on stabilizer with their 55 result. They wouldn't suggest doing anything to increase it right now because they usually try to wait until they can add salt at the same time. So if salt isn't necessary and FC is holding properly, then they don't typically do anything about CYA.

Does that have merit or is that just an example of how pool stores can keep your water all screwy?

How should I proceed?
 
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It rained more today, and then I ran some more tests this afternoon. I took a sample from the pool, and then I ran tests with my test kit as well as took it to the pool shop to see what they come up with.

TestTF-Pro ResultShop Result
FC2.53.2
CC0.5-
pH8.58.4
TA5080
CH200200
CYA3055
SALT30002900

I put 1 gal of 31.45% (20° Be) Muriatic Acid in today.

The shop is telling me that 200 is within their recommended range for CH, but PoolMath is telling me I should be at 250 minimum.

They are also telling me I'm fine on stabilizer with their 55 result. They wouldn't suggest doing anything to increase it right now because they usually try to wait until they can add salt at the same time. So if salt isn't necessary and FC is holding properly, then they don't typically do anything about CYA.

Does that have merit or is that just an example of how pool stores can keep your water all screwy?

How should I proceed?
Pool store advice is not compatible with TFP advice. We use newer science that they don’t - they are following industry standards that date back to the middle of the last century. You are going to have to decide if you want to follow their advice or the TFP way, and you’re seeing why that is now.
 
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took it to the pool shop to see what they come up with.
If you want a TFP pool (you do), then stop going to the pool store.

Their advice and testing will introduce problems and confusion. You have an excellent test kit; use it.

How are you measuring pH? If your TA is truly 50, I'm skeptical the pH is that high. Something isn't adding up. Do you have a friend or neighbor with a TF-100 or K-2006C to rule out bad reagents? Do you have a lot of water features/aeration?

If your water is clear and you pass an OCLT, ramp up your CYA to 80. Then setup your SWG to maintain FC at or above the target for your CYA level.
 
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Pool store advice is not compatible with TFP advice. We use newer science that they don’t - they are following industry standards that date back to the middle of the last century. You are going to have to decide if you want to follow their advice or the TFP way, and you’re seeing why that is now.

If you want a TFP pool (you do), then stop going to the pool store.

Their advice and testing will introduce problems and confusion. You have an excellent test kit; use it.


How are you measuring pH? If your TA is truly 50, I'm skeptical the pH is that high. Something isn't adding up. Do you have a friend or neighbor with a TF-100 or K-2006C to rule out bad reagents? Do you have a lot of water features/aeration?

If your water is clear and you pass an OCLT, ramp up your CYA to 80. Then setup your SWG to maintain FC at or above the target for your CYA level.

I'm just laying out all the data I have. I'm here because I want to follow the TFP method.

I have provided details from multiple tests with the TF-Pro kit. I also provided a picture of the Ch/pH test prior to adding the acid.

The acid definitely brought it down, and today it's showing in the 6.8.

I just received the kit brand new a few days ago. Is it common for them to ship with bad reagents? I don't know of anybody around here with a kit but I can ask.

The only water feature I have is an overflow from the spa.

I just looked up the article on OCLT. The results I have provided previously were from an FAS-DPD test, but I haven't done it as an overnight test like that. I'll do that and see how it comes out.
 
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How are you measuring pH? If your TA is truly 50, I'm skeptical the pH is that high. Something isn't adding up. Do you have a friend or neighbor with a TF-100 or K-2006C to rule out bad reagents? Do you have a lot of water features/aeration?

Should TA at 50 be holding it lower, or what makes you you're skeptical of it being that high?

I've been fighting high pH ever since this build was completed 2 - 3 months ago. It was so high at first that we had thick scaling on the walls/tile, the heater was full of scaling and it wasn't working properly, and the filter sand turned into a rock from scale/plaster dust.

This was all before I had even done any "pool school" with the builder.

They cleaned out all the equipment, replaced the sand, and got the pH down, but it creeps back up very quickly. I've put about 5 gallons of muriatic acid in over the last 30 days. Each time it'll bring it down to 6.8, then the next couple of days it looks good in the 7's, and then a couple of days after that it's back into the 8+.
 
The acid definitely brought it down, and today it's showing in the 6.8.
Add enough acid to keep the pH in the 7s. Avoid large doses of MA. If pH drifts into the 8s, add enough MA to lower pH into the high 7s.

Is it common for them to ship with bad reagents?
No.

Should TA at 50 be holding it lower, or what makes you you're skeptical of it being that high?
Rapidly rising pH into the mid-8s with a TA of 50 is unusual.

we had thick scaling on the walls/tile, the heater was full of scaling and it wasn't working properly, and the filter sand turned into a rock from scale/plaster dust.
What's your CSI?
 
Rapidly rising pH into the mid-8s with a TA of 50 is unusual.
It's a new plaster build - I believe rising pH is typical. I don't have a lot of experience with plaster pools that are 2-3 months old, so I'll have to let others chime in regarding that.
 

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I'm getting close!

We had a bunch of rain last week, and I was low on salt/chlorine. As the last bit of guidance I followed from the store I added shock to the pool on Friday, and added some salt.

I turned the SWG off when I added the shock but had the pump running ~15 hours after that. I then turned the SWG back on, but my TA, CYA, pH and Calcium were still not showing good results and the store wasn't saying anything about that.

I finally decided to trust the test kit and PM and take action accordingly.

I added some muriatic acid to bring the pH down, then I added baking soda per PM to get TA where it needs to be. Then I added stablizer per PM to get CYA where it needs to be. Then pH was a little high again, so I added just another cup of MA.

As of yesterday and today, everything is now showing in ideal range for my pool except that my FC is now too high.

FC: 12.0
pH: 7.8
TA: 70
CH: 450
CYA: 70
SALT: 3400

If I'm understanding all of this correctly that's because I shocked it and then added a bunch of salt (currently reading 3400) and had the SWG at 50%. This jacked up the FC.

The CYA/CH chart is showing I should be targeting 5 for FC based on my CYA of 70.

What's the best way to proceed from here? Should I turn the SWG off entirely or just turn it down to a low percentage? How should I adjust as I see it get back down to 10, 8, 6...should I turn the SWG back on at a low percentage while still too high, and slowly adjust the percentage until it settles around 5-6? Or should I just leave it off entirely until I'm actually testing FC at 5-6 and only turn it back on then?

Once I get this worked out I think I'll be pretty confident using the test kit and PM from this point on. Thanks again!
 
@pjt is giving you excellent advice. Your plaster is causing the pH rise. But so is the spillover. Reduce its use for a little pH relief if you can live without it. Agitating the water surface causes pH to rise. That will be the case even after your plaster cures. Acid is the price you pay to enjoy water features. PB's generally "forget" to warn you about this.

The lower you punch your pH, the faster it will bounce back. It's logarithmic, not linear. Add less acid, more often, and you'll find your MA consumption go way down. Two or three times a day if you can swing it (for now, it'll get better over time). Additionally, maintaining an even pH is best for plaster, especially new plaster. Get off the merry-go-round horse and sit in the old-lady bench seat for a while! Blasting pH like that is contributing to the problem.
 
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Oh, and don't mess with the TA right now. It'll likely stabilize on its own, and messing with it puts you back on the merry-go-round horse.

Regarding SWG and FC: test your FC at the same exact time each day. If it is low, use liquid chlorine to bring it back to your target, and then turn up your SWG by a small percent. Repeat that every day until your FC is stable at the target level. If it is high, turn off (or drastically lower) the SWG until your FC dips below target, then follow the first part of this method. It's important to top off the FC with liquid chlorine each time you find it low. If you try to adjust FC without topping it off, just by turning your SWG up and down, you'll be in for a longer haul (it's another merry-go-round dealio).
 
@pjt is giving you excellent advice. Your plaster is causing the pH rise. But so is the spillover. Reduce its use for a little pH relief if you can live without it. Agitating the water surface causes pH to rise. That will be the case even after your plaster cures. Acid is the price you pay to enjoy water features. PB's generally "forget" to warn you about this.

The lower you punch your pH, the faster it will bounce back. It's logarithmic, not linear. Add less acid, more often, and you'll find your MA consumption go way down. Two or three times a day if you can swing it (for now, it'll get better over time). Additionally, maintaining an even pH is best for plaster, especially new plaster. Get off the merry-go-round horse and sit in the old-lady bench seat for a while! Blasting pH like that is contributing to the problem.

Oh, and don't mess with the TA right now. It'll likely stabilize on its own, and messing with it puts you back on the merry-go-round horse.

Regarding SWG and FC: test your FC at the same exact time each day. If it is low, use liquid chlorine to bring it back to your target, and then turn up your SWG by a small percent. Repeat that every day until your FC is stable at the target level. If it is high, turn off (or drastically lower) the SWG until your FC dips below target, then follow the first part of this method. It's important to top off the FC with liquid chlorine each time you find it low. If you try to adjust FC without topping it off, just by turning your SWG up and down, you'll be in for a longer haul (it's another merry-go-round dealio).

Thanks for the info, but I gotta say you're throwing me off a little bit. I've been posting in threads here about comparing my tests vs. the pool store and what I felt I should be doing vs. what they're telling me to do.

I read how you need to get TA balanced before anything else because it causes the major swings - it was low and I was indeed having major swings.

I read how "the biggest mistake salt water pool owners make is not having CYA high enough" - mine wasn't high enough per TFP/PM recommendation.

I was stuck in the middle of doing what the builder / store was telling me to do based on their tests and what I was seeing with my own tests and what PM was telling me to do. The feedback here (and the experience) was that the store isn't going to give me good info. I need to trust my kit and react based on what PM tells me to do.

I did that, and now everything is nicely balanced. This is the first 2-day period where my pH held at 7.8. This makes sense to me now that TA and CYA are balanced based on everything I've read. It even rained again and that didn't pull it out of balance. I was seeing swings from high 6's to high 8's every couple of days before balancing out the other things, which again seems logical based on everything I've read and been told here.

The water also looks and feels great now. I thought it was clear before, but now it really seems crystal. I just didn't know how clear that clear should be.

But now all of a sudden you're telling me I shouldn't be messing with the things that PM told me to do, and I should have just left it alone like the store was telling me..?? I wasn't expecting that at all. o_O
 
Our pool was completed last July and I was buying Muriatic Acid by the case until the new year. It really does jump up that fast on new plaster builds. ;)

Those rains last week were pretty epic for this area and this time of year. Luckily I troll this website pretty much every day and the most I had to do was add an additional 20lbs of salt and maybe 6 ounces of muriatic acid.

BTW, for our area, Ace Hardware has the best deal on Muriatic Acid and Salt. I priced out the big box stores and Ace is not only very close, but the prices are surprisingly reasonable compared to those bigger stores.
 
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Our pool was completed last July and I was buying Muriatic Acid by the case until the new year. It really does jump up that fast on new plaster builds. ;)

Those rains last week were pretty epic for this area and this time of year. Luckily I troll this website pretty much every day and the most I had to do was add an additional 20lbs of salt and maybe 6 ounces of muriatic acid.

BTW, for our area, Ace Hardware has the best deal on Muriatic Acid and Salt. I priced out the big box stores and Ace is not only very close, but the prices are surprisingly reasonable compared to those bigger stores.
Thanks a bunch!
 
guidance I followed from the store
Stop going to the pool store. Stop soliciting their advice. It only causes more problems. Their methods of pool maintenance are very different than TFPC.

I added some muriatic acid to bring the pH down, then I added baking soda
That's counterproductive. What was the perceived problem?

my FC is now too high
Not a problem, it will quickly resolve itself.

The CYA/CH chart is showing I should be targeting 5 for FC based on my CYA of 70.
Consider that the lowest FC level you should see. There is no downside to having FC a little higher than target. It gives you a good safety margin. There is a massive downside to FC at or below minimum.

comparing my tests vs. the pool store and what I felt I should be doing vs. what they're telling me to do.
Again, stop going to the pool store.

slowly adjust the percentage until it settles around 5-6?
No problems at all letting the FC be above that level, especially when you're starting out. Use the "Effects of Adding" --> "SWG" in PoolMath to get a good estimate for how to configure your SWG runtime and %. Start with having your SWG add 3.5 FC every day and make adjustments from there.

it was low and I was indeed having major swings.
What TA value did you measure?

react based on what PM tells me to do
Temper that with common sense and a knowledge of pool chemistry. PoolMath is just a tool.

It's like driving a car and following the directions the GPS gives you:

 
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Again, @pjt is giving you excellent advice. I didn't mean to confuse things, and so won't again. pjt and I are basically saying the same things.
That's counterproductive.
pjt is referring to you trying to adjust pH and TA the way you were trying to. That's all I was saying, too. Get your FC, CYA CH and pH in the acceptable ranges that TFP recommends. Concentrate on those four things. And it sounds like you have been.
Stop going to the pool store. Stop soliciting their advice. It only causes more problems. Their methods of pool maintenance are very different than TFPC.
This is the single best piece of advice you can follow. Make up your mind which pool advice resource you want to use, only one, and ignore all the others. You cannot mix and match advice (or test results) from multiple resources. It just won't work. We recommend you pick TFP, of course, but it's up to you. The TFP forum is very different from other online pool advice forums. It is very closely moderated, and even though you might get advice from more than one of us, it will all be the exact same advice. We all learned, and then teach, only one very specific method of pool water maintenance. So when I say pick one resource, everyone on this forum, together, counts as only one!

It sounds like you're doing great. Trust your kit. Trust yourself. Trust pjt. And trust TFP!
 
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