How much Dry Acid (Sodium Bisulphate)

Problems relating to pH and total alkalinity.
Increase ph, increase TA. Reduce pH, reduce TA.
pH chemistry advice and techniques for the pool.
Denniswiseman
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How much Dry Acid (Sodium Bisulphate)

Postby Denniswiseman » Sat 08 Oct, 2011 13:14

I have been following the Dry Acid and Aeration protocol in this thread

My TA was around 180 and I have been adding 1 kilo (2.2 ibs) a time to reduce PH and TA, then I aerate
I have used about 6 kilos and my TA is at 138

The PH is reducing and being raised as it should

Am I useing to much PH reducer(sodium bisulphate) or is this the correct amount


chem geek
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How much Dry Acid (Sodium Bisulphate)

Postby chem geek » Sun 09 Oct, 2011 00:27

Lowering the TA by 42 ppm using 6 kilograms of dry acid (93.2% sodium bisulfate) would occur in a pool that was about 55,000 liters (14,530 gallons). Is that your situation? You might consider using Muriatic Acid instead of dry acid so as not to increase sulfates so much. Your 6 kilos if in 55,000 liters would raise sulfates by 87 ppm. With Muriatic Acid, you would only be increasing chloride which is far more innocuous.
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How much Dry Acid (Sodium Bisulphate)

Postby Denniswiseman » Sun 09 Oct, 2011 04:38

Hi

Thanks for the info, this forum has taught me a lot. Thanks again

My pool is 45,000 litres
How can I tell the strength of my PH minus?
How do I get rid of the sulphates?
chem geek
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How much Dry Acid (Sodium Bisulphate)

Postby chem geek » Sun 09 Oct, 2011 12:46

Your pH Minus should have ingredients on it somewhere and it will likely say "93.2% Sodium Bisulfate" though might have a lower percentage. As for sulfates, you can't get rid of them which is why you want to avoid adding too much in the first place. That is why using Muriatic Acid (31.45% or 20º Baumé Hydrochloric Acid) would be better. If you prefer Muriatic Acid that doesn't fume as much, then get half-strength (15-16% or 10º Baumé Hydrochloric Acid). You can use The Pool Calculator to calculate dosages.
Denniswiseman
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How much Dry Acid (Sodium Bisulphate)

Postby Denniswiseman » Sun 09 Oct, 2011 13:32

I dont think the pool calculator is 100%

Desired reduction in total alkalinity 40 ppm
Volume of the pool 45,000 litres
360 gr of dry acid (sodium bisulphate) is required

This was the result I got but I used 6 kilos to get about the same reduction

Try it
chem geek
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How much Dry Acid (Sodium Bisulphate)

Postby chem geek » Mon 10 Oct, 2011 01:15

In the TA section for lowering it doesn't tell you how much acid, it just says "To lower TA you reduce pH to 7.0-7.2 with acid and then aerate to increase pH." In the "Effects of adding chemicals" section at the bottom if you put in 4600 g of "dry acid" then it says this lowers the TA by 40 ppm. I'm not sure where you got the 360 g. Of course, you don't add all the acid at once anyway and instead follow the procedure of lowering the pH to 7.0 and aerating, which is what you've been doing.
Denniswiseman
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How much Dry Acid (Sodium Bisulphate)

Postby Denniswiseman » Mon 10 Oct, 2011 04:08

I am referring to the Pool Calculator http://www.havuz.org/pool-calculators.htm
Origonally I was trying to work out the amount of Sodium Bisulphate to use

For 40 ppm in a 45000 litre pool the calculation comes up at 360 gm of Sodium Bisulphate

I've tried it on two different browsers and the result comes up the same
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How much Dry Acid (Sodium Bisulphate)

Postby czechmate » Mon 10 Oct, 2011 08:37

www.poolcalculator.com has all your answers for the proper pool chemical dispensing.
Denniswiseman
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How much Dry Acid (Sodium Bisulphate)

Postby Denniswiseman » Mon 10 Oct, 2011 12:07

I am quiet happy with the way my TA is reducing
I only wanted to point out that there is on error in the Pool Wizard
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How much Dry Acid (Sodium Bisulphate)

Postby chem geek » Tue 11 Oct, 2011 00:03

Thanks for pointing out that error. I wasn't even aware of that Pool Wizard calculator as I've always used The Pool Calculator .

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