The trick while working with microorganisms (which mushroom producing fungus are) is sterile technique. Any work you do in preparation needs to be controlled in

The trick while working with microorganisms (which mushroom producing fungus are) is sterile technique. Any work you do in preparation needs to be controlled in a sterile environment. Basically all the parts where he worked under the hood are what you care about. Building a hood like that is expensive. I used a cheap approach, a plastic tub with holes cut in it and kitchen gloves taped in, inserted all my working tools and materials and sprayed it with rubbing alcohol and worked in it sealed. It is less effective than a positive pressure hood like the one built in the video, but it is reasonably effective. I know someone that doesn't even do this, she turns all fans and air conditioners off for an hour (to stop air currents), then walks deliberately, prepares her workspace which is a countertop sanitized with alcohol, and uses technique surgeons use. She also gets good results. In the wild, mushrooms send billions of spores, but you don't see the same species dominate a landscape, because they're all always competing and where one colony is successful is luck of the draw. Of course what you are going for is a 1:1 chance that you're growing what you want, so you cannot have any competition at all.