Best steps to balance pool, including adjusted TA…

[ajonarii]

My pool is about 20,000 gal and chlorinated with a SWG. I just checked my chemical levels in my pool and have come up with the following numbers after dealing with some algae. Algae is gone but there is some staining in some places.

FC - 18
pH - 7.7
TA - 90
CH - 225
CYA - 120+
Salt - 3460
Temp - 62

I know that I will need to drain probably half of my pool to get the CYA down (the level is well below the 100 on my TF-100 test, so my best guess is at least 120). I’ll get that done sometime in the near future and then rebalance everything.

My question is about the CH and TA. What would be the ideal range to shoot for? Obviously higher than I have. But is 400 really a good goal? Our fill water is hard here so we’ll se le after the drain and refill where it stands. And for TA, should I be adjusting this number based on CYA? For example, if my CYA is 80 after I drain and refill and my TA is 90…does that mean my adjusted TA is in the 60s and would possibly need to raise that level some?

 

[YippeeSkippy]

Hey there... to test your CYA when over 100+ you want to mix equal parts of pool water and tap water. Then retest using this mixture as the pool sample, then double your results. You'll get a better idea of how much you'll need drain the pool.

California water tends to be high in calcium, and have high evaporation of the pool. These two things will act on your current calcium level within the year usually. So 225ppm isn't a bad place to be coming into summer. BUT... you'll also lose calcium as you drain pool water out to lower that CYA. So when you're done with the drain, retest everything and you'll likely be adding more of a couple things. Use this as a rough guide:

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

When it comes to chemical levels and altering them- TA is the very last thing we stress about. Its sole function is to raise your pH if its on the high end. So we manage it if your pH rises quickly and needs frequent adjustment.

Holler if I missed answering anything...
Maddie

 

[pjt]

pH - 7.7

Remember, pH test is invalid when FC is greater than 10.

CYA - 120+

If you're using a SWCG, how did your CYA level get so high?

I know that I will need to drain probably half of my pool to get the CYA down

Post the results of the diluted CYA test. CYA of 80 is great with a SWCG. 90 would be manageable.

My question is about the CH and TA. What would be the ideal range to shoot for? Obviously higher than I have. But is 400 really a good goal?

Take another snapshot of your pool chemistry after the partial drain & fill. Manage pH and let the TA stabilize where it's happy. Many SWCG pools find equilibrium with TA in the 50-70 range and pH in the high 7s. What's the TA and CH of your fill water?

And for TA, should I be adjusting this number based on CYA?

No. Just use TA following the test kit directions.

does that mean my adjusted TA is in the 60s and would possibly need to raise that level some?

For a non-trichlor pool, you should (almost) never need to add baking soda.

 

[ajonarii]

Remember, pH test is invalid when FC is greater than 10.


If you're using a SWCG, how did your CYA level get so high?


Post the results of the diluted CYA test. CYA of 80 is great with a SWCG. 90 would be manageable.


Take another snapshot of your pool chemistry after the partial drain & fill. Manage pH and let the TA stabilize where it's happy. Many SWCG pools find equilibrium with TA in the 50-70 range and pH in the high 7s. What's the TA and CH of your fill water?


No. Just use TA following the test kit directions.


For a non-trichlor pool, you should (almost) never need to add baking soda.

Yeah, pH was measured using a digital reader so I’m assuming it’s close for now. I recently installed the SWG which is why the CYA is so high. I tested before but I think my chemicals were too old and it was reading closer to 80. I just got my new testing kit and it’s reading much higher now. I haven’t tested my fill water yet, but will soon. Thank you for your input and advice.

 

[ajonarii]

Hey there... to test your CYA when over 100+ you want to mix equal parts of pool water and tap water. Then retest using this mixture as the pool sample, then double your results. You'll get a better idea of how much you'll need drain the pool.

California water tends to be high in calcium, and have high evaporation of the pool. These two things will act on your current calcium level within the year usually. So 225ppm isn't a bad place to be coming into summer. BUT... you'll also lose calcium as you drain pool water out to lower that CYA. So when you're done with the drain, retest everything and you'll likely be adding more of a couple things. Use this as a rough guide:

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

When it comes to chemical levels and altering them- TA is the very last thing we stress about. Its sole function is to raise your pH if its on the high end. So we manage it if your pH rises quickly and needs frequent adjustment.

Holler if I missed answering anything...
Maddie

Thanks for your reply. I have tested my CYA several years ago using the diluted method so don’t know why I didn’t think of that this time! I’ll do that to get a more accurate idea of how much I will need to drain. Thanks!

So for TA, I would want to adjust up only if my pH was constantly rising?

 

[pjt]

So for TA, I would want to adjust up only if my pH was constantly rising?

No. High TA causes pH rise. Low TA minimizes pH rise. TA of 50 or above is fine.

PH TA Relationship - Further Reading

www.troublefreepool.com

 

[reggiehammond]

Don't forget to track CSI with a SWCG. 0 to -.6 desirable to prevent SWCG scaling.