Baking soda is used to increase pH and alkalinity.
The baking of baking soda is part of the DIY Two Part solution to increase Alk
when your pH is low. Alk
helps stabilize pH.
An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com
"Spread 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.
Once these two solutions are created, they can be added as frequently as necessary to maintain calcium and alkalinity. For further dosing instructions, see below"
Testing at midnight will give you pH results quite lower than testing just before lights out. Testing pH should always be done at the same time of day because of thiis variablity.