I have a number of 55 gallon blue barrels that were new, filled with city water through a hose made for potable water, stored off the ground and treated with water treatment/oxygenator at time of storage that are now 5+ (7 or so) years old. They have been in a climate controlled environment roughly 62-75 degrees F and protected from the sun the entire time. They are beyond the 5 years the water treatment/oxygenator stated. I really don't like the idea of just adding more chemicals and and really don't want to open them unless necessary as they have been sealed since day 1. So what now?