The goal is to grow worms with brewing grains as the feed source. With some management it would allow us to handle sudden surges or grains going bad; and more importantly to have a protein feed for our pigs. Currently the gallon of organic fishmeal that goes into our mix costs nearly as much as the pails of corn.
First, what sort of critter? Earthworms/Red earthworms? Black Soldier Fly Larvae? Something else? it probably needs to be an invertabrae of some kind.
Second, vertical silo style growth? or horizontal trench? or multiple bins or barrels?
Moisture (the grains are 72% water), Ph (may need lime) temperature, aeration, and of course the practicals: adding grains and substrate, removing vermicompost, worms etc.
If it works such a process is worth sustaining through the winter. But for now we'll wait for summer for a startup
It may also be that if earthworms are the goal, precomposting may be necessary. Perhaps precomposting could provide the heat to maintain ambient temperature.
Part of the allure is the fact that worms are 70% protein, as compared with, say, beef around 30%. A little bit could go a long way