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?
yeah sure but the breathable surface area of the jar is miniscule in comparison to its volume also CO2 is heavier than air so every pore in that mycelium block is full of CO2 and it can't go anywhere and humidity doesn't matter if the thing can't breath
Now that you mention it, I realized I just know the rate of diffusion of gas through plastic is enormous; I've done something really wrong trying to grow in vertically aligned jars!
It's all part of learning 😎