I use this method but I add it all at once. I'll try doing it slower and see if that helps. Recipe #1, Part 2: The Alkalinity PartSpread baking soda (594 grams or about 2 ¼ cups) on a baking tray and heat in an ordinary oven at 300°F for one hour to drive off water and carbon dioxide. Overheating is not a problem, either with higher temperatures or longer times. Dissolve the residual solid in enough water to make 1 gallon total. This dissolution may require a fair amount of mixing. Warming it speeds dissolution. This solution will contain about 1,900 meq/L of alkalinity (5,300 dKH). I prefer to use baked baking soda rather than washing soda in this recipe as baking soda from a grocery store is always food grade, while washing soda may not have the same purity requirements. Arm & Hammer brand is a fine choice. Be sure to NOT use baking powder. Baking powder is a different material that often has phosphate as a main ingredient.
When I mix it I put the water into a large pot then take the baking soda ash straight from the oven and mix immediately. I spread the baking soda on tin foil on a cookie sheet .... take it out of the oven, roll the foil up around the ash, close one end and pour it sorta slowly into the water with one hand while stirring constantly with the other. It also helps if you flatten any 'clumps' you may have on the sheet before pouring and mixing. This mixes it up easily and completely - then just pour it into my jugs.
I dessolved 1 cup of baking soda in 1 gallon of water without a problem. It takes a while though. I decided to make the solution a bit weaker and dose more instead of a stronger solution and smaller dose. It's all a matter of calculations.
I use a 5 gallon buckett, heater and pump. After baking it up I get to mixing it up. I Pour it in slowly and let it mix up for awhile. Its the only way I have found to get it all really disolved.
how thick are y'all mixing? I did 1 cup to 1 gal water.. no issue at all dissolving.. I'm with shelby, make it a little weaker and it's more difficult to OD...
I use recipe 1 as listed above. Its not a simple pour in and it mixes clear at all at that strength. Its fine though it raises PH some and also requires much less solution to maintain at that strength.