Nitrification bacteria are very "fragile" organisms. They are the "trout" of the bacterial groups. Water with low alkalinity may in fact allow for the nitrifiers to create a toxic environment for themselves, and limit their growth. For this reason, it is beneficial to maintain an alkalinity level above 100 mg/L. Alkalinity is NOT to be used interchangeably with the term "basic," as that is the term used to describe the opposite condition of "acidic." (Please see our Operator Notebook summary on this topic if you need more information.) Alkalinity should be at least eight times the concentration of ammonia and ideally over 100 mg/L. This value may be higher for raw wastewaters with higher influent ammonia concentrations than the "normal." The theoretical reaction shows that between 7.07 and 7.14 mg of alkalinity (as CaCO3) is consumed for every mg of ammonia oxidized. Rule of thumb is 10 to 1. The result is an overall reduction in alkalinity and a possible drop in pH if the alkalinity is low to start with.