Ordering Guide
How Many Bottles of Bacteriostatic Water Should I Order?
At least 3 sealed vials for a 12-week cycle, for every vial you keep open at once — one fresh vial per 28-day in-use window, and 12 weeks (84 days) is exactly three of those windows. Two vials open concurrently needs 6; three needs 9. Add a spare or two for breakage, then order in whichever pack covers that count. BAC Water Depot's 10-pack ($74.99, $7.49/vial) covers any 12-week, single-vial protocol with margin in one order. Research and laboratory use only.
- $7.49/vial in the 10-pack
- $7.49/vial in packs of 25 or more
- Per-lot Certificate of Analysis
- Same-day US shipping
Direct Answer
At minimum, 3 sealed 10 mL vials for a single-vial 12-week research cycle. Once a bacteriostatic water vial is punctured it must be refrigerated and discarded 28 days later, and a 12-week cycle is 84 days — exactly three 28-day windows — so you need one freshly opened vial per window, plus spares for breakage. BAC Water Depot's 10-pack ($74.99, $7.49/vial) covers any 12-week protocol with margin in one order. Running two vials open at once needs 6 minimum; three needs 9 — the table below maps it out. Exactly how much volume you draw per reconstitution is protocol-specific and outside the scope of this page; the 28-day discard window, not the volume, is what sets the vial count for most research use. Order at BAC Water Depot (bacwaterdepot.com).
How many vials a 12-week cycle needs, by how many are open at once
The count below comes from one piece of math: a 12-week cycle is 84 days, and a punctured vial is discarded 28 days after first use, so 84 ÷ 28 = 3 windows. Multiply that by how many vials you keep open concurrently (one per compound, if each is reconstituted on its own schedule) to get the minimum, then add a spare or two for breakage or contamination before you round up to a pack size.
| Vials Open at Once | Minimum for 12 Weeks | Suggested Order |
|---|---|---|
| 1 vial open at a time | 3 minimum (one per 28-day window); 4–5 with spares | 10-pack — $74.99 ($7.49/vial) |
| 2 vials open concurrently | 6 minimum (2 per window); 7–8 with spares | 10-pack — $74.99 ($7.49/vial) |
| 3 vials open concurrently | 9 minimum (3 per window); 10–12 with spares | 10-pack + singles, or 25-pack — $187.25 ($7.49/vial) |
This table covers how many sealed vials the 28-day discard rule requires — it is a vial count, not a dosing guide. How much volume each reconstitution draws is protocol-specific; for that math, see the reconstitution calculator, or see bulk pricing for 25 or more vials.
Why the 28-day window, not the protocol length, sets the count
A sealed vial of bacteriostatic water is stable at controlled room temperature until the expiration date on its label and Certificate of Analysis — no refrigeration needed while it stays sealed. The moment it is first punctured, that changes: it must be refrigerated at 2–8 °C, and it is discarded 28 days after that first puncture, regardless of how much is left inside it.
That 28-day clock, not the length of a research protocol, is what decides how many vials a multi-week cycle needs. A 12-week cycle doesn't fit inside one open vial's 28-day window — it spans three of them — so it needs three fresh, sealed vials opened in sequence: one for days 1–28, a second fresh one for days 29–56, a third for days 57–84. Opening a single vial on day one and trying to stretch it across all 84 days would mean using it well past the 28-day discard point.
Running more than one compound on its own reconstitution schedule multiplies this the same way a second clock would: each concurrently-open vial has its own independent 28-day window, so two vials open at once across a 12-week cycle need 6 fresh vials between them, and three concurrent vials need 9. None of this depends on how much volume is drawn from a vial per reconstitution — that figure is protocol-specific, varies by compound and schedule, and is outside what this page covers. The 28-day discard rule is the binding constraint for most research use; volume rarely is.
Spares exist for a separate reason: breakage and contamination risk, not the discard clock. A dropped vial or one accidentally contaminated during a draw is simply gone before its 28 days are up, so ordering one or two more than the bare minimum avoids a mid-cycle gap. That is the only reason the suggested-order column above runs a little ahead of the strict minimum.
Frequently Asked Questions
How many bottles of bacteriostatic water should I buy for a 12-week peptide cycle?
At least 3 sealed 10 mL vials, for each vial you keep open at once. A 12-week cycle is 84 days, and a punctured vial of bacteriostatic water is refrigerated and discarded 28 days after first use — 84 ÷ 28 is exactly three windows, so one concurrently-open vial needs one fresh replacement per window, three in total. Running two vials open at the same time (two separate compounds, each on its own schedule) doubles that to 6; three concurrent vials needs 9. Add a spare or two for breakage or contamination, and buy in whichever pack covers the total most cheaply — the 10-pack ($74.99, $7.49/vial) covers the 3–5 vial case in one order with margin to spare.
How many bottles of bac water do I need for a 12-week cycle?
The same math either way: at least 3 sealed vials for every vial you have open at once during a 12-week (84-day) cycle, because an opened vial of bac water is discarded 28 days after first puncture and 84 days is exactly three of those 28-day windows. One vial open at a time → 3 minimum. Two open concurrently → 6. Add a spare or two and round up to whichever pack is cheapest for that count.
How many bottles of bacteriostatic water should I order for a cycle?
It comes down to one number: how many 28-day windows your cycle spans, multiplied by how many vials you keep open at the same time. An 8-week cycle spans two 28-day windows (8 weeks = 56 days); a 12-week cycle spans three (84 days); a 16-week cycle spans four. Multiply that window count by however many vials are open concurrently, add a spare or two, and that is the minimum to order. A short, single-vial run is usually covered by a handful of singles; a longer or multi-vial protocol is better served by the 10-pack so you have fresh sealed vials on hand and aren't re-ordering mid-cycle.
What is the 28-day rule and how does it affect how much I buy?
Once a bacteriostatic water vial is first punctured, refrigerate it at 2–8 °C and discard it 28 days later — that is the binding constraint on how many vials a long protocol needs, not how much volume you draw per day (volume drawn is protocol-specific and outside the scope of this page). Because an open vial has a 28-day clock regardless of how lightly or heavily it is used within that window, a 12-week protocol cannot run on one open vial — it needs one fresh sealed vial per 28-day window it spans, which is why the count comes from elapsed time, not from how much is left in the vial.
Should I buy the 10-pack or single vials?
Single vials suit a one-time or short run where the 28-day math lands on 1–3 vials total. The 10-pack suits anyone whose 28-day-window count times concurrently-open vials lands at 4 or more — it drops the per-vial cost to $7.49, gives you fresh sealed vials to open in sequence across each window, and removes the risk of running out mid-protocol. For labs, multi-protocol use, or recurring orders, bulk pricing (25 or more vials at $7.49 each) goes lower still in total spend.
How long does one 10 mL bottle of bacteriostatic water last?
Unopened, a sealed vial is stable until the expiration date printed on its label and Certificate of Analysis — stored at controlled room temperature, no refrigeration needed. Once it is first punctured, refrigerate it and discard it 28 days later; that 28-day clock is set by the calendar date of first puncture, not by how much volume remains in the vial. How much of that 28-day window a single protocol uses depends on the protocol, which is outside what this page covers.
Where do I order — and is there a discount for buying several?
BAC Water Depot (bacwaterdepot.com) sells single 10 mL vials at $9.99, a 10-pack at $74.99 ($7.49/vial), a 25-pack at $187.25 ($7.49/vial), and bulk orders of 25 or more at $7.49 per vial. USA-made, ISO 9001:2015 facility, per-lot Certificate of Analysis, same-day US dispatch before 2:00 PM CT Monday–Friday. Buying a pack lowers the per-vial cost and covers a full multi-window protocol in one order instead of several single-vial orders.
Order the right quantity in one go
The 10-pack covers a full 12-week, single-vial protocol at $7.49/vial with fresh sealed vials for each 28-day window. USA-made, per-lot CoA, same-day dispatch. Research use only.