Day 1. How to make grain bag - Reishi growing diary by Shroomok

All you need for DIY grain bag with air filter for mushroom grain spawn. Image from forum thread Day-to-day Reishi growing diary post #3 #2

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• Day-to-day Reishi growing diary

  Day 1. Grain and Bags preparationI prepared whole rice bags. To do this I soaked the grain in water overnight and boiled it for 30 minutes. Drain, let it dry for another 30 minutes. Then, I filled autoclavable bags and made air filters for better steam sterilization and gas exchange during the colonization period.This is actually how whole, non-peeled rice in husks looks. Nothing else is added to the grain substrate.To make these bags, I used an autoclavable bag. For the air filter needed for gas exchange (and better steam sterilization), I used a plastic autoclavable cylinder plug, cotton or polyfill fiber, a protective synthetic filter paper-cloth cover, and rubber bands.I fill the bag with grain (up to 1/3 of the volume) and wear cylinder plug on a bag.Then I fill the plug with a synthetic fiber like polyfill (or cotton).After that, cover it with filter cloth (folded twice to create 4 layers) and secure it tightly with a rubber band on top.For sterilization in a pressure cooker, I cover the filters with aluminum foil to keep them dry.

Uploaded on Aug 25, 2025

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