I've tried to scale down a single fruiting medium to 100-200g, and it keeps failing time after time: at best, I get small needle-sized fruiting bodies (hypsizygus tessulatus, post picture) or primordia and then small malformed underdeveloped fruiting bodies (pleurotus eryngii, inline picture). Then development just stops. Medium is enriched (sugar) alder chips, contamination starts developing long after growth is stalled. Is it really scale problem? What's the reasonably smallest batch size?
I've grown oyster mushrooms from the grocery store on used coffee grounds and I mixed things with my hands in open air. Take the cakes out of the jar. Put them in your fruiting chamber (or plastic bag draped over it). The mycelium is a little plant animal and it breathes oxygen. You've stuffed it in an airless room with a tiny little hole. The whole body needs to be able to breathe. Not just the elbow. Oysters aren't enoki.
Thanks, I'll just try that. I know contamination starts only when the mycelium is dying; just being unreasonably careful here (I also do yeast pure cultures, habits interfere somewhat).