Smokin Moose
Fallen Cannabis Warrior & Ex Moderator
The source of nitrogen in your fertilizer affects the pH of the medium you are growing in. The standard of measure of how acidic/basic a source is, is calcium carbonate, a common water mineral. Calcium carbonate is the major contributor of water alkalinity, the capacity for water to 'soak up', or buffer, acidity in water and lead to a high pH.
Note that it is much easier to lower the pH of water through the acidity of a given nitrogen source than it is to raise it, as nitrates are less basic than ammonium is acidic.
N Source Potential acidity Potential Basicity
Ammonium sulfate---------2,200-------------0
Urea----------------------1,680-------------0
Diammonium phosphate----1,400-------------0
Ammonium nitrate---------1,220-------------0
Monoammonium phosphate-1,120-------------0
Calcium nitrate----------------0-----------400
Potassium nitrate--------------0-----------520
Sodium nitrate-----------------0-----------580
Potential acidity = # of lbs of calcium carbonate needed to neutralize acidity of one ton of source.
Potential basicity = one ton of source has same effect as this many lbs of calcium carbonate.
Note that it is much easier to lower the pH of water through the acidity of a given nitrogen source than it is to raise it, as nitrates are less basic than ammonium is acidic.
N Source Potential acidity Potential Basicity
Ammonium sulfate---------2,200-------------0
Urea----------------------1,680-------------0
Diammonium phosphate----1,400-------------0
Ammonium nitrate---------1,220-------------0
Monoammonium phosphate-1,120-------------0
Calcium nitrate----------------0-----------400
Potassium nitrate--------------0-----------520
Sodium nitrate-----------------0-----------580
Potential acidity = # of lbs of calcium carbonate needed to neutralize acidity of one ton of source.
Potential basicity = one ton of source has same effect as this many lbs of calcium carbonate.
