What Is a Flow Through Worm Bin?

If you’re a newbie Vermicomposter, you might be wondering: What is a flow through a worm bin? This is a crucial question to ask yourself if you plan to upgrade your worm farm.

What is a flow-through bin?

A flow-through worm bin is a larger container with a metal grid at the bottom. When the castings dry, a bar runs along the bottom of the bin, causing them to fall to the ground or onto a conveyor belt. These castings then fall into a catch-all pan. The bin does not have a lid, so the worms naturally move to the best food sources.

A flow-through bin needs ample space; is key to a happy and healthy worm population.

What are the benefits of a flow-through worm bin?

The concept goes that you can continuously add food to the top of the large bin, and the worms are constantly moving to the top of the bin. Red worms like to live within the top six inches of soil. The worm farmer can harvest the castings without ever having to disturb the worms. 


Most beginner vermicomposters start with an all-in-one container. However, after a few years many look for more advanced but easier-to-use systems. With a continuous flow worm bin, you will need more food to feed your worms and pay more attention to water management. Once mastered, you will have the opportunity to harvest more vermicompost without disturbing your worms.