Acid Wash

[waterbear]

The baking soda is not going to be as effective as soda ash in neutralizing the acid. I would not recommend it. You can use borax at about twice the amount of soda ash needed if you want but the soda ash should be less expensive (if you buy a 50 lb bag from the pool supply. It should be around $25-$35 in most areas.) Trying to save a few pennies here could cost you a replaster job in the end!