mrjetson707

Well-known member
Sep 7, 2021
60
Martinez, California
Pool Size
11000
Surface
Plaster
Chlorine
Liquid Chlorine
I'm new here so I hope I'm posting in the right spot. My PH is 8 so I need to get some PH down. looking online I found this: Doheny's pH Minus, 30 lb Bucket.
It seems much cheaper than muratic acid and the description says dry acid. I read on the forums here that either works. Is it cheaper because I'll need twice as much to lower the PH? is this a good deal or should I just get muratic acid? any advice with links is greatly appreciated
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
44,873
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Dry acid is sodium bisulfate. When used, sulfates build up in your water. Sulfates corrode metals and degrade concrete/plaster.

We recommend you use muriatic acid.
 

BenB

Gold Supporter
Jul 24, 2020
271
San Jose, CA
Pool Size
19500
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Jandy Aquapure 1400
Agreed. The answer to your specific question though is yes, it takes more dry acid (by weight) than muriatic acid to lower pH by the same amount. So you shouldn't be doing a $/lb comparison.

Looking at PoolMath, it looks like it's a 4:3 ratio of dry to liquid 31.45% MA. i.e. 33% more by weight dry is needed.
 
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread