Suspended solids are a common impurity in wastewater from industrial and mining operations. Safety and aesthetics dictate that all water be essentially free of suspended matter. In order to meet requirements for water clarity for reuse or discharge, the suspended solids are often allowed to settle to the bottom or float (cream) to the top of large tanks. The duration of these processes is a strong function of the particle size, e.g. larger particles settle/cream faster. Thus, if particles can be made to aggregate, the settling process is shorter and therefore the treatment operation is faster and therefore less expensive. The SZ-100 Nanoparticle Analyzer can measure the zeta potential of colloidal dispersions.