Good information. I have good luck with electrolysis using Arm & Hammer washing soda, iron electrode, and a battery charger.
See the link :
http://4strokeengine.org/gastankrepair/electrolysisrustremoval.phpReason this is safe is the chemical reactions underway:
H^2O(l) + 2Na^2CO^3(s) + Fe^2O^3(s) e> 2O^2(g) + 2H^2(g) + 2Na^2CO^3(aq) + 2Fe(s)