Test results after battling the pool for a month

[Jared Thatcher]

We have an 8000 gallon 20x48” above ground pool. A friend recommended TFP to me and I’ve been reading and studying as much as I can. I’ve been able to get the pool crystal clear for 3-4 days at a time, before it goes cloudy again. I wasn’t using a good test kit, so added and subtracted things without know what was happening. I’m worried now that my pool is basically fighting itself. Here are test results from this morning:

FC: 8
CYA: 100
TA: 110
PH: 7.2

Yesterday, I thought I would battle the TA number. Added 4lbs of PHdown to lower PH and TA. Tested this morning and showed TA at 90 and PH under 7. Decided to add Borax 20 mule (after seeing in the TFP app that it DOES NOT INCREASE TA) and added 4lbs of it. It brought the numbers right back up to where they both were.

So, couple of questions: Is my CYA too dang high? Every day I bring my FC up to 8, and the next day it’s back down to 5-6. I’m constantly having to add 20oz of liquid chlorine each day.

Next, is my TA up that high bad for us or the pool? Does it affect the FC and how effective it can be?

Finally, do I need to drain the Dang thing and start over?

Thanks!

 

[Deb04]

If your test results are from a recommended test kit, yes, your CYA is too dang high.

Which test kit did you use to get the above results.

 

[Rancho Cost-a-Lotta]

Welcome to TFP!

Please confirm which test kit you're using.

Did you complete the diluted CYA test to arrive at 100 ppm. If not, start at Step 8 in the link below:

CYA - Cyanuric Acid Test

Cyanuric acid (CYA) is the chemical name for the product commonly called “pool water stabilizer” … Read more…

www.troublefreepool.com

Your CYA is too high. It can be managed, but you've been allowing FC to drop below recommended minimum level of 8 ppm. This invites algae to come and party. If draining half the volume is possible, your pool would be much easier to manage. If not, see the chart below for recommended FC target/min levels. Since the pH test is not accurate when FC levels are above 10 ppm, test pH when FC drops below 10 ppm.



Leave the TA alone for now. Keep pH between 7.2 and 8.0. Use muriatic acid to lower pH when needed. With a vinyl liquid chlorine pool, there's no reason to fight TA.

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

Since your FC has dropped below 8 ppm, you should make sure you don't have algae by completing an Overnight Chlorine Loss Test.

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

 

[Jared Thatcher]

Welcome to TFP!

Please confirm which test kit you're using.

Did you complete the diluted CYA test to arrive at 100 ppm. If not, start at Step 8 in the link below:

CYA - Cyanuric Acid Test

Cyanuric acid (CYA) is the chemical name for the product commonly called “pool water stabilizer” … Read more…

www.troublefreepool.com

Your CYA is too high. It can be managed, but you've been allowing FC to drop below recommended minimum level of 8 ppm. This invites algae to come and party. If draining half the volume is possible, your pool would be much easier to manage. If not, see the chart below for recommended FC target/min levels. Since the pH test is not accurate when FC levels are above 10 ppm, test pH when FC drops below 10 ppm.

View attachment 595436

Leave the TA alone for now. Keep pH between 7.2 and 8.0. Use muriatic acid to lower pH when needed. With a vinyl liquid chlorine pool, there's no reason to fight TA.

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

Since your FC has dropped below 8 ppm, you should make sure you don't have algae by completing an Overnight Chlorine Loss Test.

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

So if I drain etc and get my CYA in check, will my FC level be able to hold better? Because it is constantly decreasing every night from the time I’ve been testing it.

 

[Rancho Cost-a-Lotta]

Your FC will be easier to manage. If you do have algae and need to complete the SLAM Process, a lower cya level will require less chlorine and testing reagents. Make sure you complete the Overnight Chlorine Loss Test after you do your water exchange. Most pools this time of year burn 2 to 4 ppm of FC daily.

 

[Rancho Cost-a-Lotta]

You didn't answer the question regarding a test kit. Hopefully you have a TFP recommended kit so you can accurately complete the OCLT.

 

[Jared Thatcher]

Your FC will be easier to manage. If you do have algae and need to complete the SLAM Process, a lower cya level will require less chlorine and testing reagents. Make sure you complete the Overnight Chlorine Loss Test after you do your water exchange. Most pools this time of year burn 2 to 4 ppm of FC daily.

Ok fantastic so my FC loss isn’t out of the ordinary. Good to know thank you

 

[Newdude]

Every day I bring my FC up to 8, and the next day it’s back down to 5-6. I’m constantly having to add 20oz of liquid chlorine each day.

The sun comes up everyday, even behind the clouds. You need to dose daily to slightly exceeded the UV loss (3 to 4 ppm in the peak season) to allow a little wiggle room if tomorrow is worse than today. Or a big storm hits unexpectedly, the Mrs plays hookey and has a swim day with the kids, or any other unforseen curveballs on top of the UV loss.

Once you're at one with your pool and how it behaves, you can skip every other day and double dose, or skip the inbetween day test and just dose today like yesterday, to confirm test again tomorrow.

It all hinges on reliable at home testing. Besides terrible accuracy, test strips are simply too vague. Also with terrible accuracy, pool stores just aren't open at times you need such as for the overnight / morning test, or when you finally get home from child Uber-ing every evening.

 

[Jared Thatcher]

You didn't answer the question regarding a test kit. Hopefully you have a TFP recommended kit so you can accurately complete the OCLT.

TF-100

 

[Rancho Cost-a-Lotta]

Good choice!

 

[Newdude]

Ok GREAT. 90+ is sketchy at best to read so run the diluted test listed above to prove it's actually near 100 and not way over.

 

[Jared Thatcher]

Ok GREAT. 90+ is sketchy at best to read so run the diluted test listed above to prove it's actually near 100 and not way over.

I did and I actually think it’s nearer to 110. Drain the pool here we come! I got to this number because I didn’t have the test before, and I was going out of town for 4 days. A friend suggested that my CYA was probably 0 since I had never added any CYA (which wasn’t true since I used pucks previously), so we added CYA to get us up to 60 (or so we thought). I came home and my test was here and I tested it and it was 100!

 

[Newdude]

I did and I actually think it’s nearer to 110

The diluted test has double the variance for error, but that's OK because we needed to know it was 100ish and not 200 or more.

With an above ground you can safely drain to 18 inches. You need that much water to keep the liner from floating / shifting. That'll be fine and even if it leaves you with 60 CYA, it'll be entirely manageable going forward. If the CYA was sky high, you'd have to drain and fill twice.

 

[Jared Thatcher]

The diluted test has double the variance for error, but that's OK because we needed to know it was 100ish and not 200 or more.

With an above ground you can safely drain to 18 inches. You need that much water to keep the liner from floating / shifting. That'll be fine and even if it leaves you with 60 CYA, it'll be entirely manageable going forward. If the CYA was sky high, you'd have to drain and fill twice.

Holy Crud. Drain and fill twice would suck

 

[Newdude]

Holy Crud. Drain and fill twice would suck

Yeah. You toss good water with the bad on the subsequent drains so WooHoo it's only 100 ish.

 

[Jared Thatcher]

Update!
I started with 41” of water in the pool, so I drained down to 20”. Refilled overnight, ran the filter this morning for 2 hours then tested.

FC: 5
CYA: 50
pH: 7.2
TA: 90

Now we are cooking! I added 10oz of liquid chlorine to bring it to the recommended 6 on pool math and brushed it. Saw some green cloudiness when I brushed but not much. Pool looks 95% clear. Any other additions or things I should do?

 

[Rancho Cost-a-Lotta]

SLAM Process

 

[Jared Thatcher]

SLAM Process

You think it’s going to require it? Is the green dust a sign?

 

[PoolStored]

With visible algae, follow the SLAM process...

 

[Jared Thatcher]

Update on the Slam:

Recommended FC is 20. Used granular chlorine to get it up that level. Started on Saturday. During the day FC levels are dropping to 10, which I bring back up 20 about midday. Last night/this morning did an OCLT and lost 2ppm of FC. So close! Tested this morning and FC was 10, brought back up 20 (according to Pool Math app), tested two hours later and it was at 14. Tested just now and it was down to 10ppm! Am I really losing 10ppm of FC from 6am to 3:30pm?!?