Problems with refilled pool: Water turned green after adding chlorine

[Christian B]

I live in a condominium with a 11.000 gallon in ground pool.
We recently drained and painted the pool. It then got filled up, but the pump wasn't turned on nor was there any maintenance.
Leaves build up in the bottom of the pool, stained the paint and started to turn green.
Then the pool maintenance guy told us to add 5 gallons of liquid chlorine to prevent algae. Nothing else was done in about two weeks and the maintenance guy hasn't show up anymore.
Friday I figured out how to start the pump. Removed all the leaves floating and in the bottom. I also vacuumed as much as I could.

I bought the TF-100 Test Kit. Performed yesterday the chlorine test (OTO). There was no chlorine and pH was higher than 8,2.
I purchased liquid chlorine and added about 1,5 gallons. I also purchased a powder to reduce pH and added some according to the instructions of the container (but less than needed, to prevent overshooting).

The problem is that the water turned green after adding chlorine and has stayed so since yesterday.
I don't know if the problem is due to minerals in the water, the high pH or the absence of CYA.

Today I did all the tests in the TF-100 kit:

Chlorine (OTO): over 5
PH: nearer to 8,2 than yesterday, but still above
FC: 6
CC: 0
CH: 400 (water is hard here, so I think replacing it won't lower CH)
TA: 60-70 (pinkish red)
CYA: 0 (filled the tube to the top and still could see the dot)

¿How can I turn the water clear again?
¿And in which order should I try to get the values in the desired range?

 

[JasonLion]

Welcome to TFP!

You need to SLAM the pool, see the instructions in Pool School.

The first two steps are going to be to lower PH to around 7.5, and raise CYA to around 30. Those can both be worked on at essentially the same time.

 

[pwrstrk]

Welcome to TFP !
Take Jason's advice. By the looks if it it should go quickly. Just make sure to follow the SLAM instructions to the T.
Going forward after the SLAM, if your going to use liquid chlorine it needs to be added daily. Chlorine is consumable and needs to be replaced to stay in range for the CYA level.
Here are a couple of articles to look at.
ABC'S Of Pool Water Chemistry
How To Chlorinate Your Pool
Any questions don't hesitate to ask !

 

[zethacat]

The best thing to use for reducing PH is Muriatic Acid since it will only affect your PH and TA. You should be able to find it in your local hardware store. Make sure you know the percentages of all the chemicals you buy, particularly chlorine and muriatic acid. Both come in different strengths. You want to make sure you are putting in the correct amounts. The Pool Math calculator (link at the top of the page) is your new best friend.

 

[Christian B]

Welcome to TFP!

You need to SLAM the pool, see the instructions in Pool School.

The first two steps are going to be to lower PH to around 7.5, and raise CYA to around 30. Those can both be worked on at essentially the same time.

Thanks for the help.
It seems that for SLAM I need to adjust pH first.
Since TA buffers pH changes, how long do I have to wait before testing pH again after adding the chemicals?
For the CYA, ¿can I use granulated chlorine?

@pwrstrk: we have purchased a dosing pump. It's not yet installed, but it should guarantee a daily dosage of chlorine.

 

[Kiss4aFrog]

Welcome to the forum Christian

Muriatic Acid will be less expensive and it's what most of us use. Big box store like HomeDepot or Hardware store will have it on hand.

If you use "Pool Math" it will tell you how much to add to get where you want to go. The link is at the top of the page. http://www.troublefreepool.com/calc.html

Here are some recommended chemicals that will save you some money from going to a pool store. http://www.troublefreepool.com/content/139-recommended-pool-chemicals

With pump running, wait about 30 minutes for the Ph to change before re-testing.

 

[Christian B]

Ok, thank you very much for the information.
For increasing CYA, ¿can I use granulated chlorine? ¿Or is there some other chemical?

 

[Kiss4aFrog]

You need to add "stabilizer" or CYA. There is some CYA in some granulated forms of chlorine and also in those white chlorine tablets but it's recommended you add it separately UNLESS you just happen to already have some tablets or granular sitting around. The problem with that is it takes a long time to build up the CYA that way.

Check out the "Recommended Chemicals" link above

 

[timerguy]

Use granulated stabilizer/ conditioner for cya--solid chlorine-- tabs and shock --will take a long time to get your cya up to where you need it. Use regular bleach for your chlorine. As said before, get your ph down, cya up and test and dose fc daily. Looks like your SLAM shouldn't take too long.

 

[Christian B]

I live in Chile, so I have limited options regarding pool chemicals.
I found the following: stabilized granulated chlorine based on sodium dichloroisocyanurate, rapid dissolution.
¿Could that work?

 

[Kiss4aFrog]

When you do add CYA/stabilizer you want to put it in a sock and hang it in front of your return or put it in the skimmer. If you think you are going to need to backwash within a week, in front of the return is the better choice. The CYA will also dissolve from the sock faster if you help it along by kneading the sock.
Once it's dissolved from the sock it can take up to a week to totally dissolve into the water so it's best once you determine the sock is empty to wait a week to retest for CYA so you're not getting a false reading and wasting a lot of testing chemical.
The reason for putting in front of the return is the CYA goes into the water in the pool and then dissolves. Putting it in the skimmer it dissolves but sits in the filter for a while and if you backwash you lose the CYA.

And NO, that's not my pool or my socks !!

- - - Updated - - -

I live in Chile, so I have limited options regarding pool chemicals.
I found the following: stabilized granulated chlorine based on sodium dichloroisocyanurate, rapid dissolution.
¿Could that work?

Best to post a link to it, if you can. The problem is getting enough CYA in there without going through the roof on chlorine (FC).

 

[Christian B]

http://goo.gl/5t6Heo
It's in spanish.
If it's slow to dissolve, maybe I'll add it little by little, so I don't increase FC too much and perform the SLAM once the CYA is up.

Edit: measured pH after 1,5 hours of adding chemicals. It's now a little over 7,5.

 

[zethacat]

Are you able to purchase from Amazon? You can buy pool chemicals there if they aren't available locally.

http://goo.gl/ygDRfC

 

[Christian B]

Are you able to purchase from Amazon? You can buy pool chemicals there if they aren't available locally.

http://goo.gl/ygDRfC

I purchased the test kit over Internet.
But it's too expensive for chemicals. The stabilizer costs US$ 20 in Amazon. But with shipping and taxes, it would cost me US$ 60 and would take 2-3 weeks to arrive.
I think I'll have to settle with the granulated chlorine, increase CYA slowly and then SLAM.

 

[pwrstrk]

Do what you have to do. I can understand the cost and shipping time. As long as you understand what your adding, how much your adding and what it's doing to the water chemistry you'll be fine. That's actually one thing TFP is about, knowing what your adding and the result from it.
Keep us posted on how things are going and if you need any help ask questions. ?

 

[zethacat]

Does the granular chlorine from your link list how much cyanuric acid is in it ? Knowing that would help determine how much you should use and when you should stop. Since it can take up to a week for CYA to show up on a test, you would be best off not adding more than you need as refilling with new water is the only way to lower CYA.

 

[Christian B]

Does the granular chlorine from your link list how much cyanuric acid is in it ? Knowing that would help determine how much you should use and when you should stop. Since it can take up to a week for CYA to show up on a test, you would be best off not adding more than you need as refilling with new water is the only way to lower CYA.

I will check the label in the store. Thanks for all the help and I will post an update once I have made some progress.

 

[Christian B]

I bought granulated chlorine. It says it's fast dissolving.
The label says the active ingredient is sodium dichloroisocyanurate (60% active chlorine) and that you should add 70 gram for every 10 m3.
How high can I go with the FC since the CYA is still 0? In the morning FC was 6.

 

[pwrstrk]

If your CYA level is zero you can go to 10 ppm of FC. That's shock level for zero CYA.
From the looks of what your using it's dichlor. That will have stabilizer in it. You just need to figure out how much stabilizer each dose will add. ?

 

[Christian B]

If your CYA level is zero you can go to 10 ppm of FC. That's shock level for zero CYA.
From the looks of what your using it's dichlor. That will have stabilizer in it. You just need to figure out how much stabilizer each dose will add. ��

Can't I find it out with mathematics?
Say, fill a bucket with 10 liters of tap water. Add 10 gram of dichlor. Dissolve. Take a sample of 10 ml. Dilute with distilled water (1:10 ratio?) and then take the CYA test.

If I can go as high as 10 and my FC is 6, according to the pool calculator, I should add 72 grams of dichlor.