An immersion wand device for immersion into a receptacle containing an aqueous metal halide salt solution includes an elongated housing having a handle at a first end and an immersion head at a second end, at least two iridium-coated electrodes each disposed at a distance from one another within the immersion head, a control module to control application of electricity to cause the electrodes to be oppositely charged, and a sensor in communication with the control module for determining a concentration of free available chlorine in the aqueous metal halide salt solution. The control module controls the application of electricity to the electrodes in a manner to perform electrochemical activation (ECA) of the aqueous metal halide salt solution in the receptacle to create an ECA product solution and wherein the distance between the at least two electrodes is automatically adjustable during ECA in response to a measurement by the sensor.