a method for removing an unwanted chemical from a working fluid of a system includes : 1 ) pumping into a tank a working fluid that includes an unwanted , first chemical ; 2 ) injecting into the tank a second chemical in an amount that provides or substantially provides a stoichiometric ratio relative to the amount of the unwanted , first chemical in the working fluid ; 3 ) mixing the second chemical with the working fluid in a first portion of the tank to generate a molecule that precipitates out of the working fluid and that includes the unwanted , first chemical ; 4 ) holding the working fluid in a second portion of the tank to separate the molecule from the working fluid ; and 5 ) ejecting the working fluid from the second portion . the flow rate of the working fluid and the size of the first and second portions of the separation tank are coordinated to make the working fluid take at least 4 minutes to flow through the tank .