What Should Be The Total Alkalinity?

by Janet

I just tested the alkalinity in my inground pool.

Holds 20,000 gallons.

It took 12 drops for the water tester to turn red, then it said to multiply the #of drops by 10.

So that is 120.

Is this high or low?

Thanks for the question Janet

I sounds like you're using a good Taylor test kit.

If you're comfortable with the drops, I'd suggest bumping up to an FAS-DPD K-2006 test kit, if you're not already using it.

Pool Water Testing

Water Testing Kit

Your reading is correct with getting 120.

It is just a bit high, but nothing to worry about. I've always kept my pools between 80 - 100ppm, but you can go up to 120ppm and still be safe.

When the alkalinity gets to 150ppm or above is the time to make an adjustment.

Pool Alkalinity

Total Alkalinity

You can find your post on the Q&A page in the "Alkalinity" category.

Swimming Pool Questions and Answers

Hope this helps and have a fun and safe Summer.


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Is Having Low pH And High Alkalinity Possible?

by Dave White
(Miami, OK)

Is it possible to have a low pH of about 6.6 and a high alkalinity of about 260 at the same time, or are my readings incorrect?

If so, how do you lower the alkalinity without "wacking out" the pH?

The chlorine is also still high after shocking it.

The pool is a 18'x36' with a diving end. approximatly 32000 gallons.

The water is crystal clear.

Thanks for the question Dave

The answer is yes, it is possible to have a low pH level and a high alkalinity level at the same time.

Total Alkalinity Too High..pH Too Low..Swimming Pool..

Ways Of Lowering Pool Total Alkalinity..Maintain pH Level

TA opposed to PH

As you can see many people have the same problem that you're having. Here are links to lower your alkalinity and adjust your pH level:

Swimming Pool pH Levels

Pool Alkalinity

I would suggest getting your alkalinity in line first using the above links. It will take some time and effort because it is so high, so patience is needed. It won't happen in 1 day.

Your alkalinity is at 260ppm and you need to get it down to at least 120. That's a 140ppm drop. Your're going to add about 6 gallons of muriatic acid, but not all at once. This may take a few days to get it right.

The main thing is to pour the acid in the deep end with the pump off. Very gently brush the bottom to break up any hot spots of acid. Allow it to sit for 2 - 3 hours, then turn the pump motor on and allow for 1 complete turnover of the water. This is normally about 8 - 10 hours, then retest. Try to make any adjustments at night until the alkalinity is in range.

You can use soda ash or 20 Mule Team Borax to raise the pH without much happening to the alkalinity. Remember that swimming and splashing around will cause the pH to increase.

You only need to get the pH to maybe 7.4ppm and allow the CO2 to burn off through normal swimming. This will raise the pH level. The question doesn't say how high the chlorine is, but it should come down naturally by the sun and heat. If you need the pool earlier, you can use a product called Thiosulfate.

Only use this in extreme circumstances as it may affect your chlorine reading if it's not added correctly

Hope this helps and have a fun and safe swimming season.


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What Can I Do To Lower My Alkalinity In My Above Ground Pool?

by Amanda

How can I lower the alkalinity in my above ground pool. I have read that using muratic acid will do the trick but I am afraid it will ruin my vinyl liner.

The total alkalinity is 240.

I took a water sample to two different pool stores and was told two different things.

One told me everything check out ok and the other said my alkalinity and chlorine were high.

I am new at this and at my wits end.

My pool does have a strong odor of chlorine but the water is crystal clear.

Thanks for the question Amanda

Without knowing the size of your pool, it would be very difficult to determine with any degree of certainty how much acid you'll need to lower your alkalinity (total alkalinity/TA).

But I can say this; you need to get the level between 80 - 100ppm, with 120ppm being the max, and that will take alot of pool acid from your current level of 240ppm.

Don't worry about putting acid into a pool with a vinyl liner. There's an easy way to do it.

Turn off the pump. Get a 5 gallon bucket and fill it 1/2 with pool water, then add the acid. Remember gloves, goggles, and long sleeves.

Stir with a plastic pipe or stick, and slowly pour the mixture into the pool. Gently sweep the sides and bottom to break up any hot spots.

Pool Alkalinity

Total Alkalinity

Allow this to sit for 3 - 4 hours, then turn the pump on and allow the water to fully circulate. This is about 8 - 10 hours. Retest and make another adjustment.

Do this in a series of steps. Don't simply pour 4 gallons of acid in the pool. You might overshoot the mark, then you'll need to raise it.

Get a good test kit. The Taylor FAS-DPD K-2006 kit is the one I've used since 1999.

Pool Water Testing

Water Testing Kit

When you say the chlorine was high, what was the reading? Pool store guys may not exactly know what a "high" level really means.

Hope this helps and let me know how it turns out for you.


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Chemical Levels Wrong..How To Bring Down Pool Alkalinity..

by David Murray

Please can help!!

My pool chlorine level is 8.00 after shocking, the pH is at 7.6, but the alkalinity is at 253.

How can I bring down the alkalinity 100-120.

Very Grateful,

David Murray

Thanks for the question David

Yes, your pool's total alkalinity is a bit high, so you can use muriatic acid to bring it down.

But, depending on the size of your pool, you're going to use alot of it.

The question doesn't say how big your pool is or how many gallons, but you can find the charts and information you need on these pages:

Pool Alkalinity

Total Alkalinity

Muriatic Acid

For every 10,000 gallons of water, to reduce a pool's alkalinity 10ppm, it takes 0.8 qts. or about 30 oz.

Turn the pump motor off and pour the muriatic acid in the deep end in one spot.

You can very gently brush the bottom because acid is heavier than water and will sink.

You don't want any hot spots of acid sitting on the pool bottom.

Wait about 3 hours, then turn the pump motor back on.

Allow the water to fully circulate, about 10 hours, then retest and make another adjustment.

If you need to backwash or clean the cartridges, do it before making any adjustments.

Don't try to bring the alkalinity down all at once. Do it in small and controlled doses.

It will take a few steps, and you must be patient, but you can do it with the information and links above.

Hope this helps and have a great and safe swimming season.


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Bringing Down Alkalinity In An Inground Fiber Glass Pool

by Jerry
(San Antonio)

If you have a need to drop alkalinity a 120 ppm, can you use the same formula of repeated increments of 1/4 to 1/2 gallon of acid with the pool filter off?

Should the acid amount definitely be diluted in a bucket?

Should the filter in this case be left running, rather than off for 2-3 hours, even though this delays the drop?


Thanks for the question Jerry

Yes you should follow the same procedure each time you make an adjustment to the alkalinity. Put the acid in the deep end with the pump off and very gently sweep to break up any hot spots. Leave the pump off for 3 - 4 hours, then pump back on for 8 - 10 hours and retest.

You don't need to first dilute the acid in a bucket, but if you do, be sure to go slowly when adding the acid to the deep end and also sweep the bottom.

You don't want any water movement in the pool. If you do the acid will have less effect on the alkalinity and you might reduce the pH.

I found this method to work 100% of the time, without fail, both as the YMCA pool operator since 2008 and when I had my pool route in Arizona. In both areas of work I didn't have much time to make corrections so the corrections I did make had to be right every time.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Alkalinity" category.

Check back to this post for updates or answers.

If you need immediate assistance (within 24 hrs) or for emergency personal assistance, you can make a donation of your choice and I'll answer your questions by phone.

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Hope this helps and have a great Summer.


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