I like to put lemon or vitamins (those tablets that also create fizzyness) in my water and have been wondering if it is problematic to do so in my aluminium drinking bottle. I wouldn’t normally think so, since soft drinks also often come in aluminium cans, but I’m not sure. Are aluminium salts even unhealthy?
Your aluminum drinking bottle will have a plastic lining to protect it from leeching into things anyway, so it shouldn’t really matter.
You should really get a steel one instead, regardless. The lining could tear, leech aluminum into whatever you put in there (even water over time) and make it unsafe to use.