Yup. "Alkalinity Adjuster" is nothing but a fancy expensive package for BAKING SODA! That's right, Sodium Bicarbonate. I've seen it as high as $4/lb from %!0&@rd--and $3.50/12 lbs at Costco.

That's why we call it the B-B-B method--buy your chemicals at the grocery store---Bleach, Borax and Baking Soda. And if you want pHUp!, you buy Arm&Hammer Washing Soda--usually next to the Borax!

Ben even has an article on it on the sister site, PoolSolutions.com!