To store water long term, treat it with chorine or silver tabs/drops and refresh every 6 months.
vauum sealing a intire packpack ? why would you do that ? i assum it is for you BOB, right ? A backpack which is there just in case, shouldn't be affected by abrasion. Vacuum packing doesn't protect from pressure, it will cause it ! and it won't really protect agains abrasion, since the plastic used in vacuum sealing is to thin, it also make it harder to replace stuff in the pack. I have no experians with the hydrostorm bladders, but the bladders i do have experians with ( camelbak, platypus and source ) has never leaked due to pressure ( yet ). Store the pack somewhere save and easy to acces.
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