Glouglou,
Yes, exactly! As ammonia is taken through the nitrogen cycle, acid is produced. It's basic proton chemistry. If you start with NH3 and end up with NO3- those protons went somewhere. To greatly simplify, they end up in solution as acid and this "consumes" some of the available bicarbonate. What you see is a pH drop. This makes up part of the "organic acid" that I refer to when stating that the pH/CO2/KH chart doesn't work very well. |