Which one should I adjust first

[Sunny32504]

My PH is 8.2 and ALK 90 that is not good for an AG vinyl liner but what I need to know is do I adjust the PH or ALK 1st ? Is it baking soda that increases the ALK? DO I just broadcast it over the water? What inexpensive way to lower PH? I can't remember anything I learn on here last year.
Thanks

[aylad]

I would lower the pH first, using either muriatic acid (available at Lowe's or Home Depot) or dry acid, since it'll take less to lower pH if your TA is already low. When you get it where you want it, then add baking soda via your skimmer with the pump running to increase the alk.

Janet

[Sunny32504]

Thank you . I will be going to Albertson's soon and I think they carry acid in there swimming aisle. Do I just add the acid and watch the PH for a little bit before messing with the alk. Will the acid change my Alk reading once it is added?

[KurtV]

Sunny,
Why do you want to raise your alkalinity? The typically recommended range is 80-125. Some people do say that you CAN go quite a bit higher with a vinyl pool but there's not really any need to unless you're having difficulty controlling your pH.

Your pH on the other hand is probably at least 8.2 and could be considerably higher. Most test kits only measure up to 8.2 (or less) and anything higher will look pretty much like 8.2 on the color comparator.

[aylad]

The acid will lower the alk, but it will be a temporary drop--you'll see it go back up quickly.

janet

[ksturge]

How do you keep the PH down? Do you keep adding acid? It seems so corrosive. I've added a gallon over the course of a week but my PH is still too high. How much can you add at once? It's 30,000 gallons and the acid is 31% concentrate. Also, my chlorine level is high and the pool smells bleachy and from what I've read that means I should be adding more liquid chlorine or shocking...do you think that's right?

[BillyBumbler]

If it makes you feel any better I have a new 18,000 gal pool, a week old, and I've had to add 2 quarts of muriatic already, and it's still in the 7.8 range so some more is called for. All of this has knocked down my ALK from an original level of 90ppm to 70ppm, so once I get the Ph where I want it I'll have to add a few pounds of baking soda to get the Alk back to 90 or so I suppose, and hopefully in the process not raise the Ph again. I feel like a mad scientist lately, lol.

[aylad]

How do you keep the PH down? Do you keep adding acid? It seems so corrosive. I've added a gallon over the course of a week but my PH is still too high. How much can you add at once? It's 30,000 gallons and the acid is 31% concentrate. Also, my chlorine level is high and the pool smells bleachy and from what I've read that means I should be adding more liquid chlorine or shocking...do you think that's right?

What is your TA level? To keep the pH down, you'll need to add acid, but if your TA is too low, you may be having to add more acid than necessary. Just add whatever amount you need to add to get your pH where you want it. Also, I don't know what kind of pool you have, but rising pH is something that is part of life if you have a gunite pool.

And yes, if your pool smells bleachy, you're smelling chloramines, which need more bleach to burn off. What is your Cl and CYA level?

Janet