Carrying extra water for boondocking

Over the years I have collected several 4 and 7 gallon square Aquatainers that can be stacked. I didn't believe in the predicted Y2K disaster, but right before 2000 I bought 3 unused 15 gallon white closed head barrels from a military surplus company selling Y2K survival supplies for about $18 each plus shipping in new cardboard boxes. When I bought my 28 ft trailer in 2006, I picked up a 50 gallon Snyder Industries square end agricultural sprayer tank from Northern Handyman store. They had 2 versions in the catalog. One food grade plastic and one non-food grade that was cheaper. Went to pick up a food grade at the store and they only had the non- food grade tank. However, the non-food grade had a sticker in it certifying it as food grade so I bought it. Same identical tank as food grade made on same assy line. I still have the tank, all 3 15 gallon barrels and the miscellaneous Aquatainers. I carry what is needed in the truck bed for my trip along with the 36 gallon trailer tank and 6 gallon water heater all full. I dump grey on the ground where allowed but may buy some used 15 gallon barrels to collect and haul grey water where I can't dump.