The IONIC FEATS Cleansing unit consists of a power source and an ion generator called an array. The array is placed in water. When the unit is turned on, the power supply delivers a small amount of DC current into the array which, in combination with water and sea salt causes the array to generate negatively charged ions.
Within seconds of contact with the skin, millions of these ions enter your body and begin to neutralize tissue acid waste. Negative ions attach to the positively charged toxic particles in your body and draw them out through the pores of the skin. The negative ions also alkalize the blood and tissue, unblocking your meridian channels. (Chi)
In other words the ionic foot bath is like a magnet that energizes the cells and draws out toxic material right before your eyes.