Small amount of help with opening needed

[Melissa]

Hi,
Last summer we were not able to use our pool because we could never get it balanced and the pool company sold me 100's and 100's of dollars worth of chemicals and chlorine (which it ATE but was never effective) that I think only made the problem worse. I started this season by giving the pool store one more shot but quickly realized we were on the same spending and frustration track as last year. I spent the past two weeks educating myself here at this forum (Thank you SOOO much) and have purchased the PROPER testing kit FAS-DPD and have begun the process of trying to make our pool useable again.

We have a 10,000 gallon vinyl pool (20ft round by 52" deep)
It used to be on a Tri-chlor auto feeder cartridge system. (Which worked well until last summer) I am switching to 12% liquid chlorine, the BBB method.
The pool gets constant, intense, direct sunlight as it is in the middle of a large open area. No shade at all.
We have a cartridge filter system, the cartridge is new.

The first problem I had was an overload of calcium hardness in the pool. This weekend we drained 1/3 of the pool and had fresh water delivered to replace. My new CH number is 350-375. I can't afford to replace more water at this point.

There is noticeable scaling on the vinyl liner.

These are this mornings numbers:

FC 1ppm
CC 1ppm
PH 7.0
TA 125
CYA-20???? I am guessing here as the test was inconclusive. Before the water replacement we had a CYA of about 30-35.

My plan for the day is to add Borax to bring the PH back up according to amounts rec. in the pool calculator.
Then tonight I am going to superchlorinate according to the 30PPM method listed in the table in the instruction manual of the pool testing kit by adding 2.5 gallons of 12% chlorine.

The pool is a lovely shade of cloudy turquoise.
We all desperately want to see the bottom of this pool.
If anyone has any advice or reccommendations I would love some input.
My kids are counting on me and I don't want to let them down again this summer.

Thank you ever so much,
Melissa
Central NY

 

[JasonLion]

The first step to having a trouble free pool is to get reliable test results. How are you getting your water test results? By far the best thing to do is to have your own top quality test kit. Also, please tell us more about what you mean about the CYA test being inconclusive.

You are going to want to shock the pool. But before you do that, it is important to get the test results very clear and balance the PH and CYA levels.

 

[JasonLion]

Hi,
Thank you for your reply. I purchased a testing kit from "SPS -Swimming Pool Supply Company" on line following the reccommendations of the forum here. It is a FAS-DPD kit made by Taylor.
re the CYA test:
My first test before we added 1/3 new water showed a CYA of 30-35 using the Taylor test kit. When tested now I cna still slightly see the black dot in the bottom of the cylinder even though I have run out of room to add liquid.

I am no longer relying on pool store testing and am going to use my own test ket from now on.

Thank you again of you can help.
Melissa

 

[cubbybeave08]

Melissa,
Follow the shock the pool instructions...with a CYA of 30-35 at the top of the tube, I would go ahead and call it 30...but it might be less. At 30 ppm CYA you want to shock to 12 ppm FC and keep it there overnight...if it falls off after you test in the morning or any time during the day you want to bring it up and keep it there until you are able to keep FC at 12 overnight. This is important...If if continues to fall, then you are not done sanitizing all the organics in your water. Once it holds then you are done. pool-school/chlorine_cya_chart_shock

Good Luck.

 

[PaulR]

So, you need to do these three things:
1) add 10ppm CYA to bring your level up to at least 30. (It was at 30-35 and you replaced 1/3 of the water so you're now around 20.) With full day direct sun you might want it higher, but start with 30 because you need to shock and that will be easier at a lower CYA.
2) raise your pH, around 7.5 would be good.
3) shock the pool, see the article in Pool School.

Once you have the water clear, you probably want to lower your TA. With CH 350 you're at the upper end of the suggested range so you should be able to avoid any additional scaling by keeping pH and TA under control.
--paulr

 

[cubbybeave08]

So, you need to do these three things:
1) add 10ppm CYA to bring your level up to at least 30. (It was at 30-35 and you replaced 1/3 of the water so you're now around 20.) With full day direct sun you might want it higher, but start with 30 because you need to shock and that will be easier at a lower CYA.
2) raise your pH, around 7.5 would be good.
3) shock the pool, see the article in Pool School.

Once you have the water clear, you probably want to lower your TA. With CH 350 you're at the upper end of the suggested range so you should be able to avoid any additional scaling by keeping pH and TA under control.
--paulr

Just wondering on this ...shouldn't she shock first because it actually takes a week or so for CYA to fully disapate in the water in order for the reading to be accurate when tested. Therefore I would shock first and kill what is in the pool causing the green and then worry about CYA when the pH and FC are regulated and in balance. Not that I am being disagreeable but I am wondering why when she already has a green pool would she want to raise CYA and then shock when raising CYA could take some time. Case in point...I just added 1.5 lbs of CYA last weekend added by placing the CYA in a sweat sock and tying in front of the return...This took 6-8 hours for the CYA to dissapate. Just wondering?

 

[JasonLion]

If the pool has been green for a while, I would add CYA, wait 24 hours, then start shocking.

If the pool just turned green, I would start shocking right away and add CYA at the same time. In this situation, change your FC shock target to anticipate the higher CYA level after 24 hours.

 

[cubbybeave08]

If the pool has been green for a while, I would add CYA, wait 24 hours, then start shocking.

If the pool just turned green, I would start shocking right away and add CYA at the same time. In this situation, change your FC shock target to anticipate the higher CYA level after 24 hours.

That makes sense Jason...Thanks for answering my question. Sort of seemed strange to add CYA before clearing up the problem. But your way makes good sense.

Cubby Beave

 

[Melissa]

Todays numbers

Hi all,

Thank you very much for your help so far. Unfortunately I can not get to the store to get the CYA until tomorrow, but I started the shock process last night anyway by adding 2 gallons of 12% liquid chlorine. I do understand that I need to add this asap.

Here are this mornings numbers:

FC 10 PPM
CC 1.5 PPM

PH 8.0 a false high reading due to shock (if I understand the writings about PH in my Taylor kit booklet.)

TA 125 and holding. (BY the way I also have my return jets eye turned up to aerate the water.)

I did not test any of the other paramaters at this time.

I added this morning:

10 and 3/4 cups of 12% bleach to bring the FC up to 18PPM. ( I am using the table in the back of the book that came with my Taylor test kit.)

I think that I understand that I have to get rid of CC by multiplying the CC PPM by 10 to "consume" the CC.

The water is a new color today....a lighter blueish greenish...so at least I am making progress.

I plan to retest at noon and add chlorine as well as this evening and add chlorine to keep shock levels high and to combat the CC.

We have very cloudy skies today and forecasted for tomorrow as well, so I am hoping not to suffer as much daytime loss of FC due to sunlight.

I should also mention that I am removing the cartridge in the filter and hosing it off periodically to maintain optimum filtration. The filter is "catching" quite a lot of particles.

The more testing I do and reading of my booklet in the Taylor kit the more I am understanding the process. It is hard to know what to do first sometimes and what to ignore at others, like the PH level while shocking.

Would welcome any and all suggestions or comments in order to help me learn as I try to clear off the pool.
Thank you,
Melissa

 

[PaulR]

Re: Todays numbers

TA 125 and holding. (BY the way I also have my return jets eye turned up to aerate the water.)

This is because you read about lowering TA? Aerating is the step that raises pH; it doesn't actually help lower the TA, it just makes the process of using acid to lower TA go faster. You don't want to add acid while you're shocking because you can't get a reliable pH reading.
--paulr

 

[cubbybeave08]

Quote from Melissa: I should also mention that I am removing the cartridge in the filter and hosing it off periodically to maintain optimum filtration. The filter is "catching" quite a lot of particles.

You might want to consider putting a skimmer sock in your skimmer basket...I have been running one since Saturday, and I cleaned it today...It was like peeling the lint off of a lint trap on a drier. This will save you some of the everyday cleaning while your pool cleans up.