Help with electrolysis of iron?

[cobalt_catalyst]

I am performing and electrolysis of iron to form iron(III) Hydroxide; Fe(OH)₃. I have a piece of iron as the anode and a carbon rod as the cathode, with an electrolyte of sodium bicarbonate. The power supply I am using is a 12 battery that supplies at least 10 amps but I'm not sure the exact current because my multimeter maxes out at 10 amps. Anyways what I would like to know is: How do I know when the electrolysis is complete? I know I have the iron in excess but I don't know if it will stop bubbling or give some indication when it is complete. Also what specific topic in electrochemistry does this fall into? I would like to read about it and learn how to determine these things myself.