Swimming Pool Algae

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
jgy2001
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Re: Swimming Pool Algae

Postby jgy2001 » Fri 03 Dec, 2021 20:03

Because of algae, we shocked the pool and plan to drain.
After we refill with fresh water, we use the 3 inch chlorine tablets in the chemerical in-line dispenser, with opening gap setting at 3 to 4%. Also, we heat the pool to around 84 in the days we swim.
Should be add Clorox Green Algae eliminator at this time? For every 1000 gallon of fresh water, how much should we use? Should we add this in the same in-line chemical dispenser also? Thank you for you advices.


Denniswiseman
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Re: Swimming Pool Algae

Postby Denniswiseman » Sat 04 Dec, 2021 03:36

Stop using Trichlor pucks and use liquid chlorine plain bleach, you probably have excessive CYA causing your chlorine to be ineffective

Excessive CYA renders your chlorine ineffective and you have to use more to get the same sanitation
For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm
To reduce your CYA you have to do a partial drain and refill
Continuous use of Trichlor/Dichlor will raise your CYA which means you have to raise your chlorine level as well

You need some CYA, about 40/50 as indicated in Chlorine / CYA Chart
Teapot1
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Re: Swimming Pool Algae

Postby Teapot1 » Sat 04 Dec, 2021 11:27

You shouldn't need to drain and refil because of simple algae but as Dennis said check the CYA level, this chemical controls your pool and very important to test it or get it tested AND not with test strips as these just dont work well for CYA stabiliser
I may not give you the answer you want to hear, but I will give an honest opinion of your situation as you decribe it.
jgy2001
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Joined: Thu 09 Jul, 2020 13:15
My Pool: Above Ground Pool. Tankless gas heater.

Re: Swimming Pool Algae

Postby jgy2001 » Sat 04 Dec, 2021 22:21

check the readings around 2pm:
pH 7.2
TA 160 ppm
CYA 0 ppm
TC 0 ppm
FC 0.1 ppm
TH 250ppm
May be this morning was very sunny, so we assume the sun burn off the chlorine?
Denniswiseman
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Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Swimming Pool Algae

Postby Denniswiseman » Sun 05 Dec, 2021 03:08

You are showing no CYA have you had fresh water in as it's not possible using Trichlor / Dichlor to not have any CYA
If you have changed the water get some stabiliser quick or your chlorine being burnt off will increase your chanc of algae
young707
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Re: Swimming Pool Algae

Postby young707 » Sun 19 Dec, 2021 12:37

Chorine Stabilizer is Ayanuric Acid, correct? How much the pool pH level will be caused even more lower more?
Teapot1
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Re: Swimming Pool Algae

Postby Teapot1 » Sun 19 Dec, 2021 16:12

Cyanuric acid, yes it can buffer the pH downwards from memory pH 6.8 certainly helps offset the buffer effect of too much TA
I may not give you the answer you want to hear, but I will give an honest opinion of your situation as you decribe it.

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