In parallel during the process the silver concentration within the distilled water will not be equally redistributed through the volume. It will be significantly higher closer to the electrodes. To limit the concentration of the colloid at any point you need to stir the solution during the process.
When preparing your solution give it a time to reach the concentration you are targeting. The batch cycles depends on the colloidal silver strength (ppm) you desire to achieve. Electrodes will darken in color at the end of each cycle. In order to produce high quality and pure colloidal/ionic silver water we strongly recommend you carefully clean the electrodes before each cycle (in 30 minutes intervals).