Not my words, but it's a piece of information I've saved.
"What we choose to reconstitute it with should depend on how rapidly we use the GH. Bacteriostatic water is basically sterile water with 0.9% Benzyl Alcohol added, and this Alcohol keeps anything from growing in the water, thus making it safe for injection for the longest amount of time, up to three weeks. If the amount of GH in our vial is enough to last for a few weeks at our desired daily dosage, BW is the wisest choice. For the common use for bodybuilding (2-5 IU’s a day) and the more commonly used vial size (10 IU’s), it isn’t really as critical which of the above listed dilutents are used……the vial will be used up long before bacteria or anything begins to grow in our reconstituted HGH. It is really personal preference outside of the considerations listed above."