Need some input on chlorine level?

I installed a Goldline Aquarite it is sized for a 40,000 gallon pool, I have a 26,000 g in ground vinyl pool.

The SWG has been in for about 2 weeks, when we first started the pool water was out of control very green, we should have nipped that in the but sooner.

Well the water has cleared up pretty darn good, it is at 74d.

My issue is the FC wont budge above 0 - .5?

Here are the readings
pH 7.8
alkalinity 80
cya about 80
salt 3400 ppm
Phospate was at 1000ppb now down to 500ppb after we treated it it

I have had my SWG at 100% and by all acounts looking at the SWG display it is working.

What is going on with the chlorine, do I need to shock it with liquid chlorine?

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Originally Posted by moreyes

What is going on with the chlorine, do I need to shock it with liquid chlorine?

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I would definitely shock it with liquid chlorine. YOu didn't give a CC reading, but I suspect that the problem is either that the algae bloom isn't completely dead, or your chlorine is busy fighting off the phosphate remover. (Out of curiosity, why did you add treatment for it?) Either way, your SWG is going to have problems keeping up. My advice...shock it!

Janet

I called Aquarite and they said to get the phosphate below 100ppb it was at 1000 ppb.

Can I ask you a silly question? What is the combined chlorine? and how do you get it?

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Originally Posted by moreyes

I called Aquarite and they said to get the phosphate below 100ppb it was at 1000 ppb.

Can I ask you a silly question? What is the combined chlorine? and how do you get it?

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Phosphates are usually a moot point unless you're having algae problems that you can't control otherwise...aome pool stores are famous for pushing them because they make a lot of money off of them when they're really not necessary.

Combined chlorine is chlorine that is bound up by something it's trying to sanitize, andis the primary indicator of when your pool needs to be shocked, because it indicates that there is something in your water that needs to be cleaned up. You need to use a drop-based test kit (the pool store can test for you, just don't buy all the stuff they're going to tell you that you need) to test for it. Your total chlorine is obviously the total amount of chlorine in your water. Your free chlorine is chlorine that's available to fight "gunk" in the water, and combined chlorine is the chlorine that's currently busy doing the fighting. So CC + FC = TC.

Janet

And, just to be sure it is clear -- combined chlorine is not something you want to have. Ideally, your CC reading is 0.

Hey thanks for the help. So do they actually sell a test kit for CC I see them for FC?

Pardon my pool water ignorance:confused:

moreyes, welcome to the forum!!:
As for the 'ignorance', how would you learn if you didn't ask?:confused:
A DPD test kit will allow you to detect the CC, for better results a 'FAS-DPD' kit will give more easily read results and allow you to test all forms of chlorine up to 20 - 50 ppm. You can go to www.troublefreepool.com to get an excellent test kit, which is ~;) the same as the kit everyone here uses.

Quote:

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Originally Posted by moreyes

Hey thanks for the help. So do they actually sell a test kit for CC I see them for FC?

Pardon my pool water ignorance:confused:

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To help you understand how it's done, here are the printed instructions that come with the FAS-DPDtest for testing FC and CC:


DROP TEST In8tr.15217
FAS-DPD CHLORINE (1 drop = 0.2 or 0.5 ppm) COMPONENTS:

1 x 9198 Sample Tube, Graduated, 25 mL, plastic w/cap
1 x R-OOO3 DPD Reagent #3, DB
1 x R-O870 DPD Powder
1 x R-o871 FAS-DPD Titrating Reagent (chlorine), DB

Chlorine Tests (Free & Combined) ..,/
1. Rinse and fill sample tube to desired mark with water to be tested.
NOTE: For 1 drop = 0.2 ppm, use 25 mL sample.
For 1 drop = 0.5 ppm, use 10 mL sample.

2. Add 2 dippers R-0870 DPD Powder. Swirl until dissolved. Sample will turn pink if free chlorine is present.
NOTE: If pink color disappears, add R-0870 DPD Powder until color turns pink.

3. Add R.0871 FAS-DPD Titrating Reagent (chlorine) dropwise, swirling and counting after each drop, until color changes from pink to colorless. Always hold bottle in vertical position.

4. Multiply drops in Step 3 by drop equivalence (Step 1). Record as parts per million (ppm) free chlorine (FC).

5. Add 5 drops R-OOO3 DPD Reagent #3. Swirl to mix. Sample will turn pink if combined chlorine is present.

6. Add R-O871 FAS-DPD Titrating Reagent (chlorine) dropwise, swirling and counting after each drop, until color changes from pink to colorless. Always hold bottle in vertical position.

7. Multiply drops in Step 6 by drop equivalence (Step 1). Record as ppm combined chlorine (CC).

Great thanks, my wife usally takes care of the pool but she has been traveling so I am looking at it more and more

The chlorine relationship is:

Free Chlorine (FC) is chlorine which is available to sanitize the water.

Combined Chlorine (CC) is chlorine which has combined with something else, usually nitrogen, during sanitization.

Together, they comprise Total Chlorine (TC). Simply put, FC + CC = TC.

CC doesn't have any sanitizing power, and is removed/converted/cleaned up by shocking the pool to a fairly high chlorine level, depending upon your CYA level.

Ideally, you want zero CC, and sufficient FC to maintain a clean, sanitary pool.