Automatic dosing unit selection is much more easier. the most import No. is the Capacity, ususally measureed by liter, ranges from 500L to 4000L.
While secondly you might need to pay attention to the Rated power, net weight as well as the vent, inlet, overflow, polymer outlet diameters. check details below.
Except Automatic Dosing unit, we also have simple dossolving agent device, it is also called drug-soaking bucket, which is made of PE. It consists of a stirring pump, stirrer, a dosing port, a water inlet and a cleaning port. It is much cheaper, and is suitable for small-scale personnel resident projects. Specification below for REF.