5 Year Water Supply

I have three 55 gallon plastic barrels specifically designed for water storage. In each barrel of water I added .73 oz of water preserver concentrate which I purchased in a survival store. The water preserver is supposed to keep the water safe for up to five years. Has anyone used this method of water storage and tested the purity of the preserved water?

 

Clean water has no expiry date and needs no preservatives!
Asmall amount of chemicals leaches out of plastics over time but the water needs to be stored for somewhere over several centuries to reach a level of
even minor concern!
Filter water before it go's in and its good for decades!
Taste may change due to gas separation in storage but a good shake to re-oxygenate the water is all that's needed!