Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Use Deox-C from Bilt Hamber.Does not affect paint or any other material. Dissolves rust but leaves good steel unaffected. Non-toxic and biodegradable.It will clean the interior of the tank down to clean steel.http://www.bilthamber.com/deox-c