no way man haha i am afraid of using 1 month old bac water.With opened you mean a vial you took water out? I m usi a vial I made 2 years ago... no gangrene & co... still awesome... take as my 2 cents... I could say “for ever” since there is Benzyl Alcohol... don’t know if it degrades and so on...
is my math correct? if i have a 15iu vial and add 0,8ml bac water i would get each 0,1ml with 1,875iu right?