Chlorine not registering

Causes and cures for cloudy swimming pool water.
Milky pool water, white, pink, brown, purple, black cloudy water.
duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 82
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

Chlorine not registering

Postby duraleigh » Sat 11 Sep, 2010 11:55

Yeah, get your pH up to around 7.4 or so.

Why are you returning the bleach? It is the VERY best thing you can put in your pool for chlorination.

If your CYA is 40 as you report, you will need probably 2ppm of chlorine each day for the remainder of the swim season and bleach is the best way to add it.


24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
James Watson

Chlorine not registering

Postby James Watson » Sat 11 Sep, 2010 14:48

Your use of trichlor is what has caused your pH to drop so much. Trichlor also adds a lot of cyanuric acid. If you continue to use trichlor as your primary source of chlorine, your cyanuric acid will quickly get too high. I recommend that you only use trichlor when your cyanuric acid needs to be raised and the pH needs to be lowered.

As Duraleigh said, bleach is the best thing to use for routine chlorination.

For increasing pH, I advise against using pH increaser (soda ash, sodium carbonate). Soda ash causes the water to be cloudy, and could react with any metals in the water.

If you need to raise the pH, I recommend that you aerate. To aerate, point your return eyeball towards the pool surface. This will agitate the water and cause carbon dioxide to be off-gassed.

If aeration does not increase the pH enough, add about 4 pounds of baking soda and continue to aerate. Dissolve 2 pounds of the baking soda in 4 gallons of water and pour the solution into the pool. Do this twice to add 4 pounds.

You can also use Borax to raise your pH. Dissolve 1 pound of the Borax in 4 gallons of water and pour the solution into the pool. Do this twice to add 2 pounds.

With the FAS-DPD test kit, you will be able to keep your chlorine at the right level, and you should rarely, if ever, need to shock. In most cases, you would only have to slightly increase your chlorine for a short time instead of shocking.

You should maintain an FC of about 7 to 8 percent of your cyanuric acid level at all times. Your overnight FC (free chlorine) loss should only be about 1.0 ppm or less, and your CC (combined chlorine) should be 0.5 ppm or less.

The times you will need to elevate your chlorine will be when:

1) Your FC is allowed to drop below 7 % of your cyanuric acid level for more than 24 hours. Or
2) Your overnight FC loss is more than 1.0 to 1.5 ppm. Or
3) Your CC is higher than 0.5. Or
4) You get algae, or cloudiness you suspect is algae.

Elevated chlorine levels should be about 20 to 25 % of your cyanuric acid level. Shocking, which brings your chlorine level to about 40 % of your cyanuric acid level, should be avoided if possible.

Bleach is the best thing to use. Calcium hypochlorite should be avoided.
shhurs
Pool Care Proficient
Pool Care Proficient
Posts: 31
Joined: Tue 07 Sep, 2010 09:50
My Pool: 16 x 32 above ground, Kayak, vinyl liner, Haywood pump, cartridge filter
Location: St Louis MO

Chlorine not registering

Postby shhurs » Mon 13 Sep, 2010 13:40

My chlorine has gone up and held steady for 3-4 hours and then drops overnight. I do cycle the pump off during the night.

And, to confirm what I'm reading by duraleign and J Watson - you want me to continue to add 2 ppm of the chlorine bleach daily (I'll use the pool calculator to figure the ounces out). I guess I'll need to go back to the 1 gallon per hour to get the level back up first? Why does it drop after several hours?

I assume it's as safe to get in the pool with the addition of the bleach as it is the "pool store products?"
duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 82
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

Chlorine not registering

Postby duraleigh » Mon 13 Sep, 2010 14:21

Why does it drop after several hours?
Chlorine is the one item that you test for that is a consumable item. pH, TA, CYA, and CH are reasonably constant but chlorine is depleted continuously and must be replaced

Importantly, it is depleted by ONLY two things.....1)sunlight and 2)organics (especially algae) that get into your water
24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
James Watson

Chlorine not registering

Postby James Watson » Mon 13 Sep, 2010 14:37

If you are using trichlor in a feeder, then the chlorine only feeds while the pump is on. When the pump is off, the trichlor continues to dissolve in the feeder, and when the pump turns back on, the concentrated chlorine in the feeder is added to the pool. This will cause what you are experiencing.

My advice is to stop using trichlor. Allow the tabs in the feeder to fully dissolve until they are gone, and then do not add any more to the feeder. Then, use bleach to maintain a Free Chlorine level of 25 % of your Cyanuric acid level until:

1) Your water is clear and
2) Your overnight FC (Free Chlorine) loss is less than 1.5 ppm and
3) Your CC (Combined Chlorine) is 0.5 or less.

You need to use the FAS-DPD test kit to do this properly. You should run the filter 24/7 until you achieve the above three things. It is safe to swim if your FC is at 25 % of your cyanuric acid or less, and the CC is 0.5 ppm or less.

The best time to add the bleach is at the end of the day after all swimming. You can add bleach before people swim. Add the bleach, wait 1 hour and retest. As long as the FC is at 25 % of your cyanuric acid or less, and the CC is 0.5 ppm or less, it is safe to swim.

Once you achieve the above objectives, you should maintain a Free Chlorine level that is at least 7.5 % of your cyanuric acid level. You should continue to monitor your overnight FC loss and CC levels and elevate your FC to 25 % of your Cyanuric acid level any time they are in excess of the previously mentioned standards.

You should continue to monitor your pH, Total Alkalinity, Calcium Hardness and Cyanuric acid. You should maintain them at the levels recommended by the pool calculator. You should maintain a CSI (Calcite Saturation Index) of about -0.4 to 0.0.

Have you received your FAS-DPD test kit yet?
James Watson

Chlorine not registering

Postby James Watson » Mon 13 Sep, 2010 14:45

As duraleigh noted, chlorine is consumed on a continuous basis. You will need to add chlorine every day to maintain a proper level. Test every day and add the proper amount of bleach to maintain the recommended levels. Once you get used to doing this, it will only take a few minutes a day.

How clear is your pool now?
shhurs
Pool Care Proficient
Pool Care Proficient
Posts: 31
Joined: Tue 07 Sep, 2010 09:50
My Pool: 16 x 32 above ground, Kayak, vinyl liner, Haywood pump, cartridge filter
Location: St Louis MO

Chlorine not registering

Postby shhurs » Mon 13 Sep, 2010 14:48

it has actually improved. Not as sparkling as it was before the whole stain / remover incident, but on the road to looking better.

should the chlorine level continue to drop after a few hours of halting the bleach or eventually remain constant?
James Watson

Chlorine not registering

Postby James Watson » Mon 13 Sep, 2010 15:06

During the day, sunlight will consume chlorine. The key test is the overnight test because there is no sunlight to consume chlorine. If the overnight test shows a loss of 1.5 ppm or more, then you know that there is still algae or other organics that need to be oxidized.

You could raise your cyanuric acid to about 60 ppm if you want better sun protection, but I wouldn't go too much above that.

There are various factors that determine FC loss rate, such as water temperature and sunlight duration and intensity, but you can expect to lose a few ppm per day under normal circumstances.

Introduced organics from swimmers and leaves etc. will consume chlorine and might cause some CCs to develop.

As you begin to get used to testing on a daily basis, you will learn what your particular loss rates are under various circumstances and you will be able to determine how much bleach to add so that the level is still good when you test the next day.

For your pool, I would anticipate that you would probably need to add about 3 quarts per day to maintain proper levels once you get your water clear.
duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 82
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

Chlorine not registering

Postby duraleigh » Mon 13 Sep, 2010 15:10

chlorine is depleted continuously and must be replaced
That rate of depletion depends on how much organics are in your pool and sunlight.

The sunlight (UV rays) loss of FC is diminished drastically by having the correct level of CYA in your pool but you will ALWAYS lose some FC in a 24 hour period. Most pools seem to lose about 1-3ppm if they are algAe free.

You should go to Troublefreepool.com and read Pool School..."The ABC's of Pool Water Chemistry"
24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
shhurs
Pool Care Proficient
Pool Care Proficient
Posts: 31
Joined: Tue 07 Sep, 2010 09:50
My Pool: 16 x 32 above ground, Kayak, vinyl liner, Haywood pump, cartridge filter
Location: St Louis MO

Chlorine not registering

Postby shhurs » Mon 13 Sep, 2010 21:40

oh my goodness is my head spinning now! I guess that's why you guys are the chemist and well I'm not!!!

I left at 6 am and got home at 8 pm and still haven't been out to the pool and it's dark so on to another day. Trying to keep up with this situation when I'm not at home every day is tough. I likely won't get back at it until Wednesday. This process takes dedication that's for sure. And since I work it's difficult to try and achieve good results when I'm not here 24/7. Is it like starting over each and every time my chlorine doesn't hold, or is there a cumulative effect with the bleach I've already added? Have I done anything to oxidize the contaminant, and not starting from square one each time.

So, continue with the bleach additive; let feeder run out; run pump 24/7; and once stabilizes then I should be good to go back to my feeder method? Course, swim season will be over probably in less than a month. So, is it all worth it now.

I certainly respect the knowledge you have on this subject and I hope I understand it all. Many thanks.

Return to “Cloudy Pool Water”

Who is online at the Pool Help Forum

Users browsing this forum: No registered users and 0 guests