Guides
Bac water, explained for buyers.
Short guides to the questions that decide an order: which size, how long an opened vial lasts, what a COA should show. Each starts with a two-line answer. For quotable one-paragraph answers, see Quick answers.
Which Bac Water Size Should You Buy: 3, 5, 10 or 30 mL?
Pick the bac water vial you finish within 28 days of the first puncture. Sizes, water per kit and price per mL compared, and when a small vial beats a big one.
Read the guide →The 28-Day Rule for Opened Bac Water Vials
Why an opened bac water vial is dated and discarded 28 days after the first puncture, what counts as day one, and how unopened and single-use vials differ.
Read the guide →How to Check a Bac Water COA Before You Buy
What a useful bacteriostatic water certificate of analysis shows — lot, dates, measured results against limits — the red flags, and how to get the COA of your lot.
Read the guide →Bac Water, Sterile Water or Acetic Acid Water: Which Diluent to Order
How bacteriostatic water, sterile water and 0.6% acetic acid water differ — preservative, re-use, pH — and how to choose the one your material's documentation asks for.
Read the guide →Buying Bac Water Online in the US: What to Check First
A short checklist for buying bacteriostatic water online in the US: concentration, size and kit count, published prices and shipping, dispatch time, lot COA and a seller you can reach.
Read the guide →