1. Start with about 1100 ml cold distilled water in a container big enough to handle all the effervesence - maybe a gallon or two.
2. Add 450 grams of Potassium Carbonate mono with stirring until dissolved.
3. SLOWLY add 400 gm of oxalic acid to the potassium carbonate solution with stirring, waiting each time you add the acid until the bubbling subsides. Continue until all of the oxalic acid has been added.
4. Add water to bring total volume to 2 liters. Check the pH at this point. It should be near 7.0 (neutral). Now add more oxalic acid in small amounts and keep checking the pH. When you get the pH to about 6.0, you’re done.
Is the advantage to this in the cost? Or just easier than having it shipped?