Alkalinity out of control


New member
Jul 18, 2007
Hello all, I'm new to the forum.

I have been battling my alkalinity since last summer. It seems that I can pour gallons of muratic acid in the pool to lower the alkalinity, which is does for a short while (a few days), all the while lowering my ph. Then after up it goes again.

I have tried to maintain it, but the acid doesn't seem to last???

I have an inground plaster pool approx. 30k gal.s. The pool is about 20 yr.s old and I plan on getting a replaster job after the summer season. We have lived in the house for five years, and in that time I have never drained the pool. I know that my hard water level is high, but we will be draining the pool in a few months, no sense in doing it now.

I should say that the first three years we lived in the house, I hardly ever had to adjust the alkalinity or the ph. Everything was easy to maintain. Not any more though.

Does anyone have any clue what may be going on in my pool.

As an aside, I had a pool guy replace some equipment a few weeks ago. I asked him about the alkalinity and his response was, don't worry about it. He says that he never even bothers testing for it. Is this crazy???

Thanks for the help!


Mod Squad
LifeTime Supporter
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TFP Expert
In The Industry
Apr 1, 2007
Sebring, Florida
Hitman, welcome to the forum.

Alk can only be permanantly lowered thru aeration.

Lower your pH to 7.0 - 7.2

Then, start aerating the water in your pool. Sprinkler, fountain, air compressor, whatever. There are several examples on this forum of ways to aerate. Your Alk will start to lower and your pH will start to rise. Lower pH again with muriatic back down to 7.0 - 7.2. Continue to aerate and your Alk will continue to lower.

You don't say how high your pH is but you can lower it to whatever you want thru this method and it will stay there (for the most part).

And, yes, the pool guy is crazy.


Well-known member
May 18, 2007
Enid, Oklahoma
Here are the procedures for lowering ALK.

PoolForum Sticky

I followed these procedures and was able to lower my ALK from 290 to 90 in about four weeks. I turned all my return jets towards the surface and one of them is a spa jet. I may have had some help from all the rain we received. :-D