High pH, Low FC, Just Right TA - new pool owner SWG

[Lmj011]

We installed our 22,000 gallon pool end of May. We have a Pentair IC 40 SWG and just recently concluded our included pool service. The last few weeks I’ve been learning and testing/treating the pool a few days before the pool folks were set to arrive and I always had similar results:

pH around 8-8.2 or higher (pool guy data)
FC around 1-2
TA is almost always 7 drops - so 70ppm

I’ve been adding the recommended amount of muriatic acid in ounces to try and get to a 7.6 or so and while I’ve only been testing weekly (maybe that’s my issue?), it doesn’t seem to budge from hovering around an 8.

My SWG shows 3650ppm and is running the pool at 80%. The spa was set to 0 so I bumped it up to 15% but it hasn’t been on. We run the waterfalls daily from 6am to 10pm. No heater running (hello Texas summer!). Pool pump runs 8am to 6pm.

Please help! I was trained in college chemistry so this should be right up my alley but I’m getting frustrated. Also not a fan of these color estimations for pH - do digital ph readers work? Thanks y’all!

 

[HermanTX]

Welcome to TFP.
Running your waterfall for 16hrs is driving up your pH.

PH TA Relationship - Further Reading

www.troublefreepool.com

PH - Further Reading

www.troublefreepool.com

TFP has a different methodology than what your pool service provides.
We are based on the FC/CYA Levels relationship. We also believe that self-testing using a proper test kit is best.
Test Kits Compared
Since you are new to pool ownership, You should be testing at least every 2nd day to understand what changes in your pool.

Your FC is too low but you have not provided a test for CYA so we do not know what the target should be.
Your TA is great at 70 (if that is accurate) but aeration caused by waterfalls running constantly are driving increases in your pH.

You should also obtain the PoolMath app to track your test values and monitor the overall chemical balance of your pool.

BTW digital pH do work if your get the proper type and keep it calibrated. Many use the Apera pH60 model but there are other models similarly priced. A cheap pH meter does hold calibration and soon find yourself doubting the results.

 

[casiokid]

Also, the “Spa” setting for your IC40 refers to how much chlorine should be produced when the spa is on.

You want to set this low, say 2% so when you’re in the spa, you’re not getting blasted with a ton of chlorine in that smaller body of water.

 

[Lmj011]

Thank you both so much! My test kit does test for CYA I’ve just never used it. I’ll update the spa settings, change the waterfall timing and retest.

I’m pretty confident in TA as that’s the one you count the drops and it takes 7 drops to change the color from green to essentially clear. 8 if you want it red.

I also use the pool math app which is awesome. So helpful! Thanks again!

 

[PoolStored]

I’m pretty confident in TA as that’s the one you count the drops and it takes 7 drops to change the color from green to essentially clear. 8 if you want it red.

Add drops until the color does not change. Subtract that last drop.

 

[Mdragger88]

What exact test kit do you have?

 

[HermanTX]

I’m pretty confident in TA as that’s the one you count the drops and it takes 7 drops to change the color from green to essentially clear. 8 if you want it red.

Using the Taylor reagents - the TA test stops when it turns cherry red - so your TA is at least 80 if it turns red on 8th drop. It may go a lighter red if you add another drop so that is why it is important to count drops until the color does not change further.

I also use the pool math app which is awesome. So helpful! Thanks again!

Go to settings and turn on CSI. When you add your test results then CSI will calculate.
Please post full results
FC
CC
pH
TA
CH
CYA
SALT
Pool Temp.
CSI

 

[Lmj011]

Using the Taylor reagents - the TA test stops when it turns cherry red - so your TA is at least 80 if it turns red on 8th drop. It may go a lighter red if you add another drop so that is why it is important to count drops until the color does not change further.


Go to settings and turn on CSI. When you add your test results then CSI will calculate.
Please post full results
FC
CC
pH
TA
CH
CYA
SALT
Pool Temp.
CSI

Sorry was out of town. Here’s my results —-


FC — 3.0
CC — not sure what this is??
pH — 8.2
TA — 70
CH — 262
CYA — 50
SALT — 3750
Pool Temp. — 87
CSI - 0.26

 

[Lake Placid]

We installed our 22,000 gallon pool end of May.

I’ve been adding the recommended amount of muriatic acid in ounces to try and get to a 7.6 or so and while I’ve only been testing weekly (maybe that’s my issue?), it doesn’t seem to budge from hovering around an 8.

In addition to your waterfall running, new plaster will drive PH rise for a while. It’s not out of the norm and will slow down over time. Adjust your PH more frequently.

 

[HermanTX]

Sorry was out of town. Here’s my results —-


FC — 3.0
CC — not sure what this is??
pH — 8.2
TA — 70
CH — 262
CYA — 50
SALT — 3750
Pool Temp. — 87
CSI - 0.26

CC is combined chlorine and is tested directly after FC using the same sample.
Please read

CC - Further Reading

www.troublefreepool.com

Also, some pool stores provide you Total Chlorine (TC) - CC = TC-FC
Can you advise what test kit you are using?


For a SWCG you are bordering on the minimum FC level. Suggest you raise your FC to the 4-6 level. In summer it is always best to be on the high side.
You could also raise your CYA to 60 or 70 and that will also require you to increase the FC target range

Your CSI should be negative with a SWCG system. Your pH is driving the CSI calculation to be positive.
Continue to test your pH daily and adjust to keep it in the 7.3-7.6 range. Reduce the use of any water features as aeration also causes pH to rise

 

[Lmj011]

CC is combined chlorine and is tested directly after FC using the same sample.
Please read

CC - Further Reading

www.troublefreepool.com

Also, some pool stores provide you Total Chlorine (TC) - CC = TC-FC
Can you advise what test kit you are using?


For a SWCG you are bordering on the minimum FC level. Suggest you raise your FC to the 4-6 level. In summer it is always best to be on the high side.
You could also raise your CYA to 60 or 70 and that will also require you to increase the FC target range

Your CSI should be negative with a SWCG system. Your pH is driving the CSI calculation to be positive.
Continue to test your pH daily and adjust to keep it in the 7.3-7.6 range. Reduce the use of any water features as aeration also causes pH to rise

I’m using an HTH 6-way test kit. Tested again today and have negative CSI but it’s telling me to add stabilizer because my CYA is too low? I did do this prior to filling the pool this morning so I may be even more off.

FC - 3.0
pH - 7.8 (I think turning off the fountains was key here!)
TA: 70 ppm
CYA: 40 ppm
CH: 262 ppm
Salt: 3800
CSI: -0.15
Water Temp: 82

Should I add stabilizer?

 

[HermanTX]

I’m using an HTH 6-way test kit. Tested again today and have negative CSI but it’s telling me to add stabilizer because my CYA is too low? I did do this prior to filling the pool this morning so I may be even more off.

FC - 3.0
pH - 7.8 (I think turning off the fountains was key here!)
TA: 70 ppm
CYA: 40 ppm
CH: 262 ppm
Salt: 3800
CSI: -0.15
Water Temp: 82

Should I add stabilizer?

With a SWCG, target the CYA level to be 60-80ppm. So buy granular stabilizer and put in a sock, then hang in front of a return.
Continue to monitor pH.
Everything else looks great.