In order to directly electrochemically monitor the system with a potentiostat, we used a smaller reactor with a shorter distance between electrodes, and thus less resistivity overall. This two chamber PTFE reactor had a 20-mL capacity and a magnetic stirrer in the ocean side (Figure ). The same electrolytes, ion exchange membrane and minerals used with the large glass reactor were used here. For these experiments we chose several fixed voltage (-0.5V and -2V), as well as an 'expected' current (10 nanoamperes; based on the resistivity of the system, and the potential difference) and a greater 10 microampere current.