For bact water I just use distilled water, add .8 ml of BA to 10 ml of distilled water. filter through a .22 whatman filter into a new sealed vial and voila, you have bact water.

Some guys will vent the vial and "bake" it at 140 for a couple hours but a .22 whatman will filter any bacteria out. I have never done it and been doing this since the mid 90s with never a prob.