View source for Tutorials/Agar/Storing Cultures

Once you have a clean, strong culture, keep a copy safe. Storage gives you a backup when a grow contaminates, a clean starting point when a working culture weakens, and something to share with other members.

Good practice is to keep a '''master culture''' in long-term storage and a separate '''working culture''' you actually use. Never start a grow from the master directly; make a working copy from it instead.

== Storage methods ==
{| class="wikitable"
! Method !! How long !! Effort
|-
| Spore prints || Years || Low
|-
| Agar plates in the fridge || 1–3 months || Low
|-
| [[Tutorials/LiquidCulture/Making and Using LC|Liquid culture]] in the fridge || Several months || Low
|-
| Agar slants in the fridge || 6–12 months, sometimes longer || Medium
|-
| Agar plugs in sterile water || A year or more || Medium
|}

== Agar slants ==
A '''slant''' is a test tube partly filled with agar that was left to set at an angle, giving a long sloped surface. The small opening and tight cap make it far less prone to drying out and contamination than a plate.

=== Making them ===
# Use screw-cap culture tubes, glass or autoclavable plastic. Loosen the caps a quarter turn.
# Fill each tube about one-third with hot, liquid [[Tutorials/Agar/Making Plates|agar]] (a slightly firmer recipe, with a bit more agar powder, holds up better).
# Pressure cook upright in a jar or rack.
# While the agar is still liquid, lay the tubes down propped at an angle so the agar sets as a long slope. Tighten caps once cool.

=== Inoculating them ===
In a [[Tutorials/Basics/Sterile Technique|still air box or flow hood]], transfer a small wedge from the leading edge of a clean plate onto the slope. Let it grow at room temperature until it covers most of the surface, then move it to the fridge.

== Agar plugs in water ==
This method keeps cultures alive for a long time with almost no attention.
# Fill small vials or tubes with distilled water and pressure cook them.
# Cut several small cubes of colonized agar from a clean plate and drop them into the water.
# Cap tightly, wrap the cap with Parafilm, and store at room temperature or in the fridge.

To revive, fish out a cube with a sterile tool and set it on a fresh plate.

== Storage tips ==
* Keep cultures at about '''35–40°F''' (2–4°C). Don't freeze them unless you've prepared them specifically for freezing.
* Some warm-weather species don't tolerate cold storage well. If a species struggles to restart after the fridge, keep its backups at cool room temperature instead.
* Seal plates with Parafilm and store them upside down in a zip bag.
* '''Label everything''': strain, transfer number or source, and date.
* '''Refresh''' every 6–12 months: revive the stored culture on a fresh plate, confirm it's clean, and make new storage copies from it.
* When you revive any stored culture, let it warm to room temperature first and expect it to be sluggish for the first few days.

{{Cultivation}}
[[Category:Tutorials]]
[[Category:Agar]]