When troubleshooting nitrification, it is essential to first ensure your basic general parameters are applicable. The pH should generally be kept greater than 6.8 and less than 8.3. Alkalinity, which acts as the “food” for nitrifying bacteria, requires a residual of greater than 75 mg/L in the filtered mixed liquor at all times. It is important to test alkalinity residuals in the filtered mixed liquor rather than the final effluent, as alkalinity may be recovered if denitrification occurs in the clarifiers.Sludge age is highly temperature-dependent. In colder weather, it should generally be greater than six to eight days, while in
