This is an outdoors & chemistry question.
I have an old and functional water bladder, shown below. On it, there are markings that coffee, beer, wine, hot drinks etc. must NOT be stored inside, only water.
While I realize that wine is acidic, damaging the bladder and becoming poisonous, beer seems to me quite close to water. Furthermore, I indend to test it with weisbeer, which does not contain such a large amount of gases as to explode.
Would be safe for me to store non-fizzy beer for up to a day every day in a "do-not-store-beer-inside" water bottle and then safely drink it?