Abstract: The present disclosure provides for a system and method for treating a wastewater stream by measuring the level of a contaminant, adding a treatment fluid and mixing them in an inline mixer and then by means of a custom spray head inside a mixing tank. The treated effluent from the tank can be further treated in a similar fashion in successive treatment tanks before being discharged. The contaminant can be an out-of-range pH, particulate matter or dissolved metals.