Quote Originally Posted by chem geek View Post
Or you could use 72 pounds of boric acid. At DudaDiesel this is $65 for 55 pounds plus $45 for 25 pounds plus shipping for the 55 pounds so $110 plus shipping (or 3 25 pounds would be $135 with free shipping). AAA Chemical has $60 for 50 pounds so $120 for 100 pounds plus shipping. The Chemistry Store has $89.10 for 55 pounds and $27.75 for 15 pounds so that's $117 for 70 pounds plus shipping.

Personally, I find using boric acid to be a lot easier since it's just one chemical to add. It didn't used to be as inexpensive as Borax plus acid, but these days it's a lot closer and I think a lot more convenient. Be sure to get granular and not powdered -- the powdered version tends to sit on top of the pool. The granular still dissolves very quickly and is gone with some light brushing. The effect on pH only drops it from 7.5 to around 7.2 when you add 50 ppm borates (the quantities above).
I switched to using boric acid last year. Much more convenient and I don't have to deal with handling MA.

Btw, I don't know how much adding borates has to do with this, but I noticed that since lowering my TA to 70-80, my pH settles at 7.5 to 7.6 with the SWCG running and doesn't rise any higher. I didn't have to add any MA all last season nor so far this season.