Questions on levels: Measured all the chemicals, now what?

May 12, 2017
10
Phoenix/Az
Hello, I was recommended this website by the previous homeowner. I have been coming up to speed on learning about pool care, mostly by reading this site. I have been working on balancing all the chemicals, but would like advice on any adjustments I should make. My main concern at the moment is calcium and TA (I may be missing other things too and just don't know it, so please point out anything I should work on managing).

Location: Southern AZ
Pool: 14,000 gallon pebble tec pool with a SWG (T-Cell-9 running at ~80%)
Test Kit: New Taylor kit (tossed all the old test chemicals because I did not know the age/storage conditions)
FC: 4.6 ppm
CC: 0 ppm
PH: 7.8 (have to add acid weekly)
TA: 160 ppm
Calcium: 750 ppm (eek)
CYA: 60~70 (hard to tell exactly when dot disappears)
Salt: 2900 ppm

During a recent trip the salt cell shut off due to "low salt" and I came back to a bit of a mess, but now water is clear and great color. T-Cell had gotten a lot of deposits and had to clean with 4:1 mixture of water to muratic acid. This has been a bit of an ongoing problem.

Any help/advice is appreciated!
 
"PH: 7.8 (have to add acid weekly)
TA: 160 ppm"

There's a familiar problem. Last year my pool drank Muriatic acid like a drunkard on free beer night. Reduce PH to ~7 with acid (+/-50 ounces should do it), then aerate until the ph is back up to about where it is now, and repeat. Looks like you'll need to do that 4 or 5 times.
 
With the high CH, you really need to try to keep the pH below 7.5. Having the high CH and high pH is why your SWG cell is scaling up.

I agree do a quick OCLT to make sure there is nothing in the water.

Then you need to make sure your keep that pH down.

Where did the salt reading come from? The SWG or a test kit?
 
Welcome to the forum. Did you do this: You pass an OCLT (ie overnight FC loss test shows a loss of 1.0 ppm or less). Without SWG running of course.

Nope, I have not run this test. I will do it after the weekend when the pool is not in use.

- - - Updated - - -

Forget the TA for now, it can be adjusted later and will come down some on it's own anyway. What is the CH and TA of your fill water

Fill Water:
CH: <200 ppm, I will rerun if you need a precise number. I rushed it and over shot the color change.
TA: 110~120 ppm

- - - Updated - - -

With the high CH, you really need to try to keep the pH below 7.5. Having the high CH and high pH is why your SWG cell is scaling up.

I agree do a quick OCLT to make sure there is nothing in the water.

Then you need to make sure your keep that pH down.

Where did the salt reading come from? The SWG or a test kit?

Salt reading came from the SWG control unit and verified with pool store test. I tried to buy the salt test chemicals, but the local Leslies does not carry it.

- - - Updated - - -

"PH: 7.8 (have to add acid weekly)
TA: 160 ppm"

There's a familiar problem. Last year my pool drank Muriatic acid like a drunkard on free beer night. Reduce PH to ~7 with acid (+/-50 ounces should do it), then aerate until the ph is back up to about where it is now, and repeat. Looks like you'll need to do that 4 or 5 times.

Thank you for the solution to the high TA. Online all I read was I needed to drain the pool some, but due to high cost of H2O here I am trying to avoid that. I will keep this trick in my back pocket for now :)
 
With the high TA and CH of our fill water here in AZ, you kind of expect both to start high, even on a fresh fill.

Let's start with an Overnight Chlorine Loss Test (link here: Pool School - Perform the Overnight FC Loss Test (OCLT)) and then we can talk about your options. My pool is currently at 500ppm CH after a full drain a year ago, it's just a fact of life here. You'll do fine at higher CH levels but you're going to have to watch your CSI number (Calcium Scaling Index) - you can calculate it using PoolMath (link at the top of the site) - make sure to enter every field, including salt and pool temp. TA plays a big role in that, so once we've made sure nothing is growing in your pool, we can address that issue.
 
With the high TA and CH of our fill water here in AZ, you kind of expect both to start high, even on a fresh fill.

Let's start with an Overnight Chlorine Loss Test (link here: Pool School - Perform the Overnight FC Loss Test (OCLT)) and then we can talk about your options. My pool is currently at 500ppm CH after a full drain a year ago, it's just a fact of life here. You'll do fine at higher CH levels but you're going to have to watch your CSI number (Calcium Scaling Index) - you can calculate it using PoolMath (link at the top of the site) - make sure to enter every field, including salt and pool temp. TA plays a big role in that, so once we've made sure nothing is growing in your pool, we can address that issue.

Sounds like a plan. I will test tonight and let you folks know the results.
 
With the high TA and CH of our fill water here in AZ, you kind of expect both to start high, even on a fresh fill.

Let's start with an Overnight Chlorine Loss Test (link here: Pool School - Perform the Overnight FC Loss Test (OCLT)) and then we can talk about your options. My pool is currently at 500ppm CH after a full drain a year ago, it's just a fact of life here. You'll do fine at higher CH levels but you're going to have to watch your CSI number (Calcium Scaling Index) - you can calculate it using PoolMath (link at the top of the site) - make sure to enter every field, including salt and pool temp. TA plays a big role in that, so once we've made sure nothing is growing in your pool, we can address that issue.


Ok,so I think I may have done something wrong, because I measured my FC at 10PM (1hr after I shut off SWG) and 3:30AM and both readings were the same. It came out to 3 ppm at both time intervals. Same location in the pool, both SWG and pumps shut off for the duration. I repeated the morning test 3 times.
 

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A zero drop is a great thing! Awesome.

Based on an 80 degree pool, with the numbers at the top of the thread, you're at high risk for scaling.

So the next thing to do, if you don't plan to drain/refill to lower the CH, is get the TA down to around 60-70 to reduce that scaling potential. Doing that plus keeping the pH around 7.6-7.8 will get your water close to balanced.

The best way to lower TA is here:

Pool School - Lower Total Alkalinity
 
A zero drop is a great thing! Awesome.

Based on an 80 degree pool, with the numbers at the top of the thread, you're at high risk for scaling.

So the next thing to do, if you don't plan to drain/refill to lower the CH, is get the TA down to around 60-70 to reduce that scaling potential. Doing that plus keeping the pH around 7.6-7.8 will get your water close to balanced.

The best way to lower TA is here:

Pool School - Lower Total Alkalinity

Sounds like a plan. That will be my next course of action. Thank you all for walking me through this.
 
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