Muriatic acid with vinyl liner

[gorocket1981]

Hello,

I will confess I would like to follow the advices and use the products recommended but I am a bit afraid of muriatic acid. Everybody around me tell me that it is very dangerous ... I am not stupid, it is an acid so it is not a toy like other chemicals but is it at that point dangerous?

Is it good to use only with concrete pool? Hardware store told me that it is a product only sold to deeply clean concrete.
Will this harm a pool with vinyl liner?

 

[mknauss]

You add muriatic acid slowly at the return stream of water into the pool. It is diluted immediately.

As you have an above ground pool that I assume you drain every year, you can use Dry Acid, or sodium bisulfate if you wish. If it builds up it could damage the metal in your heater, but hopefully you do not need much acid over the summer months.

 

[gorocket1981]

Usually I use dry acid but I wanted to follow the best recommendations. I drain it for the winter. I think that I pour around 7 to 8 kg of dry acid during all swim season last year. My pH is always on the high side like 7.8 to 8.0. It is still on the high side this year.

But last year I was always trying to lower it to 7.4 or lower. At the end, it never really worked. It was a constant battle with TA.

For this year I will try to be more zen with it and accept it higher and I will stop trying to have a low pH and and TA over 100. We will see how I can manage this.

 

[LFrankow]

I use MA on my pool for PH reduction, no problem at all.
I dilute it in a plastic juice container before pouring it into the pool. I fill to first line with water, then carefully add acid after to second line I made, stir with a paint stick, then slowly pour into the pool in front of the return with pump running.
I did drop my TA to around 60-70 a few years back, it really helps control the upwards drift of PH.

 

[gorocket1981]

OK. Before I was under the impression that it was a crime to let the TA drop lower than 100. Each time it was reaching 100 or lower, I was rising it.
Now, following what I read, I will try to be less control freak on TA. I was sure it was as important as the other parameters. I think that I was giving TA too much importance.

 

[mknauss]

TA can fall as far as 50 ppm without issue for your pool type.

 

[Torturedzen]

I'm also using MA and if I could also ask a question (sort of on-topic)... When I began prepping my pool about a month or so ago, my TA was about 160. I've been adding MA to lower the pH to 7.2, aerating to raise pH, testing TA levels, repeat...repeat.
Today my tests show TA levels of 100. Goal is 70-80. I'm making progress but is this normally how long it takes to bring it down with MA? I've gone through 3+gallons. The dude at Menards just smiles at me every time I show up to buy more!

 

[mknauss]

Depending on your fill water, which I assume is the same 160 ppm TA, it will take time, as you are dealing with any fill water you add along with what is in the pool.

Once your TA is below 100, only drop your pH to 7.6 from 8. That will slow the TA drop and should slow the pH rise.

 

[Richard320]

I'm also using MA and if I could also ask a question (sort of on-topic)... When I began prepping my pool about a month or so ago, my TA was about 160. I've been adding MA to lower the pH to 7.2, aerating to raise pH, testing TA levels, repeat...repeat.
Today my tests show TA levels of 100. Goal is 70-80. I'm making progress but is this normally how long it takes to bring it down with MA? I've gone through 3+gallons. The dude at Menards just smiles at me every time I show up to buy more!

It can take a while.

Secret: down below the table on PoolMath you will see Effects Of Adding Chemicals. Once it calculates a dose to lower pH, go see what effect it will have. Pay attention to the caveat: the pH change they give down there will only work in very limited circumstances, but the TA drop is right on. So you may find that the acid to drop the pH will only lower TA by 6 or whatever. If you're a little above your test result alrteady and then you drop only 6, you may not even be able to see a reduction. But you'll be able to reassure yourself when it happens.

Also test the refill water. Your pool got above 100 TA somehow. If that refill water is 200 TA and you add 3" to a pool that averages 5 feet deep, you've just added 10 ppm TA.

 

[Torturedzen]

Thanx for the replies. I'll test my fill water later tonight.