water is not bac water it is sterile water... big difference, sterile water will not preserve the way bac water will.

best way to do it is to get some bac water.... mix 1ml of bac water with hcg draw up 1ml mixture of hcg/bac put into sterile 10ml vial. top off vial with desired amount of bac water
if you fill it to the brim it will be 1ml=150iu. it will keep for up to 60 days in the fridge