High CYA

[mbusd]

Hello All,


New to the forum and pretty new to pool ownership. We had pool service included for a few months and now that it's ended we decided to DIY. We went to a local pool store last week and they told us that our chlorine level was at zero and our PH was high. This was after a week of no pool service. They were only coming once a week so we assumed we only need to check it once a week. Oops. Anyway, the guy at the local store gave us GLB Granular which is 99% Sodium dichloroisocyanurate dehydrate and says 56% available chlorine. Also gave us some muriatic acid.

He told us to add 2.5 to 3 lbs of the the glb granular and I think 1.5 gallons of the muriatic acid(will have to double check with the husband). He said it would be safe to swim in within 45 minutes. Tested the water about 3 hours later and chlorine levels were crazy high. We started off with one of those water testers you find at lowes(Chlorox brand). PH was fine.

So next morning we went in to Leslie's instead and these were our results(last Sunday):

FAC 10(again, she said it was off the charts so it was probably higher?)
TAC 10
CH 190
CYA 50
TA 110
pH 7.4
Copper 0
Iron 0
TDS 600
Pho 200

She had us add Chlorine neutralizer to bring levels down. Tested it a few hours later, Chlorine was still high, though it did go down noticeably. Haven't added anything else since then but we've been swimming and temps have been in the 100s. Oh, and we do have one of those little chlorine tablet floaters.

Went in this afternoon to have our water tested and these were this week's results:
FAC 0
TAC 0
CH 140
CYA 100
TA 90
pH 8
Acid 1
Copper 0
Iron 0
TDS 800
Pho 500

Just got our TF-100 kit, so haven't had a chance to read up and use it yet. From what I understand, high CYA is not a good thing? Will we have to replace water? The water is clear. Also, what would make the CYA go up like that within a week? Or could it be that testing at Leslie's is inconsistent? I'm going to try to get a test in tomorrow morning to see if there is a difference but I'm hoping for some advice and maybe some reassurance that we are ok to swim in our pool while we get this figured out?

Sorry, I know this is long, but not sure what info will be the most helpful.

Thanks!

 

[jblizzle]

Welcome to TFP!!!

It is still sunny ... get outside, get a sample of water and do the tests in the TF-100.

We do not trust pool store testing, so I am going to ignore those.

3 pounds of the Dichlor powder would have only added 8ppm of FC and 7.3 ppm of CYA to your size pool.

 

[duraleigh]

but not sure what info will be the most helpful.

Break out that TF-100. It may be a bit intimidating but the results are worth it. You';ll never have to second guess the management of your pool.

Post up the results.

 

[pooldv]

Welcome to TFP!

It is safe to swim when
PH is 7.2 to 7.8
Water is clear
FC is above minimum and below shock level for your CYA, Chlorine CYA Chart

Which CYA test do you pick? 50 or 100?

Chlorine level is set based on CYA and the Chlorine CYA Chart, it must be kept above minimum at all times to keep the pool sanitized and algae free.

 

[mbusd]

Ok, took out the test kit for the first time this morning and this is what I got:

FC .5
CC 0
TC .5
CH 675 Am I supposed to keep counting until the entire thing turns blue, or just until I start seeing blue show up in the cylinder?
TA 170 Same as calcium...as soon as I start seeing red? Or does all the water have to turn a bright red color?
CYA 65ish I also tested the standard just to make sure I'm doing this somewhat correctly.

Should I be testing out in full soon? Or like in a shaded patio? Indoors? Time of day? Should I make sure my pump is running? How many times/day should I be testing when starting out?

Oh, and when I add chemicals...does the order matter? Should I add chlorine before muriatic acid? I entered my numbers in the pool calculator so I know how much to add. Bleach...just plain ol' Chlorox is good?

Thanks again for all your help!

 

[jblizzle]

Always add drops until the last one causes no further color change and do not count that drop.

Pump needs to run an hour or so before testing.

 

[Richard320]

Ok, took out the test kit for the first time this morning and this is what I got:

FC .5
CC 0
TC .5
CH 675 Am I supposed to keep counting until the entire thing turns blue, or just until I start seeing blue show up in the cylinder?
TA 170 Same as calcium...as soon as I start seeing red? Or does all the water have to turn a bright red color?
CYA 65ish I also tested the standard just to make sure I'm doing this somewhat correctly.

Should I be testing out in full soon? Or like in a shaded patio? Indoors? Time of day? Should I make sure my pump is running? How many times/day should I be testing when starting out?

Oh, and when I add chemicals...does the order matter? Should I add chlorine before muriatic acid? I entered my numbers in the pool calculator so I know how much to add. Bleach...just plain ol' Chlorox is good?

Thanks again for all your help!

On the color-changing tests, you add until you get no more change, then deduct the useless drop. So at 15 drops TA you see pinkish, 16 is pink for sure, 17 gets really bright Barbie pink, 18 makes no change, Deduct the useless drop. 17. TA is then 170.

Calcium, when you're getting high numbers like that (mine is much higher) take a breather from the drops every ten or so and swirl and extra minute. When it first turns blue, stop the drops and swirl another minute. It will either get bluer or revert back to maroon or pink. Keep going until it doesn't change, and deduct the useless drop as above.

The CYA test needs to be done in full sun. The rest should be done in good light, but it's okay to move to a comfortable spot and have a seat. Maybe set a cold drink nearby. Just don't confuse the sample cup with the drink cup. I've gotten inches from my lips before I caught myself... I do my tests at the patio table and only move to the sun to use the CYA view tube.

You can test whenever is convenient for you. Just try to do it at roughly the same time every day so you get a good feel for how much FC you lose every day, and make sure the water has had some time to mix first. So pump on an hour or so before you grab your sample.

Once a day is plenty when you're starting. Just pH, TA, and FC every day. CH can be done weekly or every other week. Cya maybe once more in a week and then monthly after that, unless you've done some adjusting via draining and refilling. You'll soon learn your pool's appetites and be able to predict your readings before the first drop is dripped.

 

[mbusd]

Thanks everyone, for all the help! I'm already feeling more confident and will test once more this evening now that I've read all your advice. I feel so much more confident with my own test results rather than waiting to make a trip to the pool store, which I don't trust anymore after just 3 trips there. I was done with Leslie's yesterday when they told me that my CYA level was high, probably caused by the GLB granular the other pool store recommended to me, but then she told me to go ahead and keep using it until I run out. As far as that GLB Granular( 99% Sodium dichloroisocyanurate dehydrate and says 56% available chlorine), should I just avoid it all together? I was told by Leslie's that it raises CYA and can cause issues with calcium in plaster pools...but then she told me to keep using it until I run out so I'm not really confident in her advice. I went out and purchased liquid chlorine today, as I don't want to add the GLB if that's going to increase my CYA too much. Oh, and I also removed the little chlorine tablet floater. Not sure what that was for since it didn't seem to be contributing any chlorine to my pool anyway.

 

[YippeeSkippy]

" Also, what would make the CYA go up like that within a week? Or could it be that testing at Leslie's is inconsistent?"

Funniest thing I've read today!!

 

[mbusd]

" Also, what would make the CYA go up like that within a week? Or could it be that testing at Leslie's is inconsistent?"

Funniest thing I've read today!!

Ha! Well, I am curious now. Why are pool store tests inconsistent? Is it because the water isn't being tested right away? Or are their tests designed so that their is always a recommendation? They have always been nice and they seem very helpful...but even with one test on my own kit I already feel more confident in the results.

 

[pooldv]

Lots of reasons, here are a few
Poorly trained kids working over summer
Imprecise samples/dosing
Bad lighting
Not thoroughly rinsing out containers with the last customer's water in it

Who can add some more?

 

[YippeeSkippy]

Lots of reasons, here are a few
Poorly trained kids working over summer
Imprecise samples/dosing
Bad lighting
Not thoroughly rinsing out containers with the last customer's water in it

Who can add some more?

In a hurry as other customers are waiting
improper pool info (size, type of pool) used when giving directions on how much of x chemical to add