Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
That’s is not bad at all. Great product you may want to consider for light de-rust is Bilt Hamber Deox-C. It’s safe on paint as well and is bio-degradable so you can dispose easily after use (or just store it for further de-rust duties).
Never line your tank it will be the last time you use the tank, when it fails and it certainly will it cannot be removed, so I recommend an acid wash with pool acid diluted 50:50 followed by neutralize with baking soda solution which should be left in the tank for 1 daySent from my iPhone using Tapatalk