Most resources online for vermicomposting units focus around a Rubbermaid bin or tower system. I found this could be labor intensive, and could not process large amounts of waste without multiple bins. A more efficient system to operate on a larger scale is a flow-through system. This is essentially a large bin where waste is added to the top and castings are harvested from the bottom leaving the worms undisturbed inside. However these commercial systems can be expensive. Using the same basic principles one can be made with readily available and recycled materials.