What are your thoughts on aerating your water to get rid of Co2 ? I heard that Co2 produces carbonic acid that can drive Alk and PH down. I have this problem with my water in my freshwater tank and my pond. Someone told me this, I don't know all the in's and out's of the logic. I have PH out of my tap at 9, but some how it will go down in the tanks and pond.