I got to the shop today and the tank was cracked open, already cleaned ready for welding. Although it is in perfect outside condition, the inside was so rusted, that the steel was corroded, not to the point of holes, but left a lot of marks on the metal. I'm thinking sand-blast. Once we had a shipment of steel beams that were scubadiving in Mobile when the Katrina hit, no acid or basic wash helped, pure old scaler, grinder and sand blast. Anyway, talked to the galvanizers, $1.00 for each pound of weight of the tank (make that $30.00 for galvanizing) 15 days and I'm worry free. Hope it works. In the meantime I'll try to find Red Kote, just in case.