Spawning to Bulk
The transition from lab to harvest. Preparing the environment for the final flush.
Sanitizing Your Tubs
Don't just wipe them down. I recommend a bleach dunk: Fill a large, clean trash can with water and add 1 cup of bleach per 10 gallons. Dunk your tub for a few minutes, then wipe them dry with a clean cloth towel (paper towels are not necessary).
- Dishwasher Tip: Clear polypropylene tubs can even be run through the dishwasher for a deep clean. if you want you can add a small amount of bleach to the wash by putting a small glass of bleach in the silverware container and it will get mixed in during the cycle.
The Boiling Method (Pasteurization)
Boil your substrate in a large pot. Once it hits 210°F (99°C), hold that temperature for 30 minutes. Turn off the heat, cover with a towel, and let cool completely (usually overnight).
The Oven-Bake Method
For PP5 tubs, you can bake the substrate directly in the tub:
- Mix substrate to field capacity in the tub.
- Bake at 250°F (121°C) for 3 hours.
- Let cool naturally in the oven overnight. Rapid cooling or heating jars can cause them to crack.
Field Capacity & Ratios
Firm Squeeze Test: Substrate should release only a few drops of water when squeezed hard.
Ratios: I usually run a 1:1 or 1:2 ratio of grain spawn to substrate for fast colonization.