Balancing TA/CH/CYA fluctuations

[Jacquelyn1215]

Since mid-May, we've noticed some fluctuations with our TA, CH and CYA. Our pH has pretty consistently run high since we opened our pool in March 2022 so it's normal for us to add muriatic acid ~2x/week. However, recently our TA dipped, CH increased and CYA dipped. Our TA and CH have been consistent (within recommended ranges) since we opened the pool, but we did have to add stabilizer last summer to boost our CYA. When we recently noticed the TA dip we first tried turning on our water feature more frequently but it didn't budge so my husband recently added alkalinity increaser (can't remember exactly what it was) and it brought it back up and we're currently sitting at 50/60, so I guess still in okay range.

I guess my question is, when thinking about TA/CH/CYA, what to tackle first/in what order? Test logs attached. Many thanks!

 

[mknauss]

Share your Poolmath logs. Go into your App, Settings, Share.
Thank you.

 

[Jacquelyn1215]

Share your Poolmath logs. Go into your App, Settings, Share.
Thank you.

Logs are attached.

 

[mknauss]

They are. Many will not open random pdf files. So sharing is safer. Also, it does not show what you added.

 

[duraleigh]

good numbers. I think your fluctuations come from just being a little new to this type testing,

Nothing in your numbers is bad but if you are looking for a "what to tackle first"........

1. Keep a close eye on pH and FC......at least every other day for a while more. You want pH in the 7's and FC around 4-6 ppm......not lower than 4

2. I would bring CYA up to 60 for the Austin Summer. It goes down on it's own but VERY slowly

3. You CH is a little high but not alarming. 300 or so would be better. What is the CH of your fill water?

4. I would leave TA alone.........you are fine.

mknauss is right about sharing your logs within TFP.......it's better

 

[Jacquelyn1215]

They are. Many will not open random pdf files. So sharing is safer. Also, it does not show what you added.

ah, got it. Here you go: PoolMath Logs.

 

[mknauss]

With what you have added, acid and baking soda, the CYA cannot have gone up. It could go down, very slightly over the time period, but not up.
Do you have a lot of aeration occurring? Your pH should not be rising hardly at all if your TA is at 40 or 50. Adding baking soda to raise your TA then adding acid to lower your pH is the pool store hamster wheel. If your TA gets as low as 50, your pH should stop rising.

The CH level is essentially level as the tests are all within the testing error for that test. You eventually want to use a large rain event to change out some of your water. Your fill water likely has elevated CH.

 

[Jacquelyn1215]

good numbers. I think your fluctuations come from just being a little new to this type testing,

Nothing in your numbers is bad but if you are looking for a "what to tackle first"........

1. Keep a close eye on pH and FC......at least every other day for a while more. You want pH in the 7's and FC around 4-6 ppm......not lower than 4

2. I would bring CYA up to 60 for the Austin Summer. It goes down on it's own but VERY slowly

3. You CH is a little high but not alarming. 300 or so would be better. What is the CH of your fill water?

4. I would leave TA alone.........you are fine.

mknauss is right about sharing your logs within TFP.......it's better

I just did the CH test on our fill water and it was 70.

 

[Texas Splash]

Water temps are increasing which brings with it the increased chances for scale. Since your CH is on the higher end (650), it's important to keep the pH under 7.8. I would add some muriatic acid now to lower the pH to about 7.5-7.6. The TA is fine, but each time you control the pH it might pull the TA down. That's good as long as the TA does not fall below 50.

Your FC is low. Add some liquid chlorine right away and get the FC up to about 6-7 ppm. Before I went to my SWG, I maintained a CYA of 60-70 this time of year all the way through Sept. My pool gets full TX sun all day long. If you find your FC falling too fast, it could be that you don't have enough CYA in the water.

Word of caution, if you ever suspect algae (cloudy/hazy water, seen green "poofs" when brushing, etc) do an Overnight Chlorine Loss Test before increasing the CYA in the slim chance a SLAM Process is required. When you are sure there is no chance of excessive organics/algae, raise that CYA and keep the FC balanced to that CYA as noted on the FC/CYA Levels to prevent algae.

 

[Texas Splash]

Thank you for posting the test logs link in that post above. Another TFP tip: Go into your Poolmath APP settings. Scroll down and there is a toggle to "Share with TFP profile". Something like that. This way all we have to do is put our mouse/curser over your avatar and see your Poolmath logs (link). You won't have to copy & paste anymore.

 

[Jacquelyn1215]

Water temps are increasing which brings with it the increased chances for scale. Since your CH is on the higher end (650), it's important to keep the pH under 7.8. I would add some muriatic acid now to lower the pH to about 7.5-7.6. The TA is fine, but each time you control the pH it might pull the TA down. That's good as long as the TA does not fall below 50.

Your FC is low. Add some liquid chlorine right away and get the FC up to about 6-7 ppm. Before I went to my SWG, I maintained a CYA of 60-70 this time of year all the way through Sept. My pool gets full TX sun all day long. If you find your FC falling too fast, it could be that you don't have enough CYA in the water.

Word of caution, if you ever suspect algae (cloudy/hazy water, seen green "poofs" when brushing, etc) do an Overnight Chlorine Loss Test before increasing the CYA in the slim chance a SLAM Process is required. When you are sure there is no chance of excessive organics/algae, raise that CYA and keep the FC balanced to that CYA as noted on the FC/CYA Levels to prevent algae.

To bump up our FC we just increase the output of our SWG. For example, yesterday I changed it from 25% output to 50% output which brought it from 3 yesterday to 5.2 this morning. So we don't typically use liquid chlorine (not sure if this is right or wrong!). This has been one of the trickier things (FC) with the output %. I feel like we're frequently tinkering with it because if we bump it up our FC skyrockets and then gets too high... not sure if you have any recommendations on that. It isn't a big deal to do since it's simple with the app, but like I said, I feel like we are playing around with the output % semi-regularly.

Have the CYA still dissolving in the sock suspended in the skimmer but I suspect we'll likely need to add more. We had to do this last summer but are always ultra-conservative and add it slowly as my understanding is if you get it too high, there's really no way to get it out (or, it takes a long time).

 

[Texas Splash]

not sure if you have any recommendations on that. It isn't a big deal to do since it's simple with the app, but like I said, I feel like we are playing around with the output % semi-regularly.

I try to keep my adjustments fairly small as to not have a yo-yo effect, If my FC seems a bit low, I'll add a little liquid to get it where I want it quickly, then do a small % output increase to try and maintain it.