Domestic Vermicomposting

Domestic Vermicomposting

A few years ago I started vermicomposting and only just now realized that I never wrote about it, so here we are.

I wanted to have compost worms, and I needed a system that would operate all year round even when it was 20 below outside.

This meant a system that was capable of being moved indoors during the winter months. And that meant a clean and odor free system.

After some research I arrived at a stacking 5 gallon pail system like in the video below:

That worked for a few months and then I discovered some fatal flaws in the system advocated in that video. The weight of the worms and bedding and castings forced the pails into each other to the point that I couldn't get them apart when the lower one became full of leachate. I eventually did separate them, but it was a huge stinking mess. I also found that there was not enough air getting into the composting chamber and things were getting a little anaerobic.

My solution was to drill a lot more holes not only in the bottom of the pails, but in the sides as well. That fixed the smell issue, but it introduced a new problem. When I cleaned out the system, I couldn't line up all the holes again so that the airflow was maintained.

After a lot of trial and error I present to you MkIII of my worm tower. It is dialed in and problem free. The system uses 5 pails. Two of these are actual composting compartments (one for active composting and the other for finishing off), but you can add more as desired.

One pail (the bottom one) is the sump which collects leachate, and I have a spigot (a tap) mounted in the bottom so I can drain it off without disassembling the system. This is a huge improvement. I also added a sighting tube to the sump, and drew a line around the outside with a permanent marker at the point where the bottom of the upper pail is positioned. This means I can tell at a glance if the sump needs emptying. It is another huge improvement and it prevents stinky leakage / overflows.

Two of the pails are used as spacers. This prevents the pails from jamming together when there is weight in them.  A spacer is made by cutting the bottom of a pail off like shown in the image on the left. A spacer goes between every composting pail you have in the system, and also between the lowest composting pail and the sump.

Once all the pails are stacked together in order, I then drilled the breathing holes so that there is a clear path for air to travel into the composting chambers through multiple pail sides.  Since these pails stack inside each other, the hole has to pass through the wall of two pails, and also a spacer depending on where the hole is.

I then drilled some larger holes that will be used to align and lock the pails together. In the image, you can see I use a piece of scrap coaxial cable for the job, but it can be anything really.  The important thing to note here is that the two holes are bigger than the ventilation holes so they can be easily identified during reassembly.

Since these holes go all the way through the pails, alignment and reassembly is simple.

The locking mechanism also prevents the pails from separating when you go to move the system, since we now have these spacers that prevent the pails from fusing together. If you don't have the locking pins, then the pails will separate during transport and make a huge mess.

It's probably worth mentioning that these locking pins are installed at every spacer, and there are two locking pins per spacer - on opposite sides from each other.

When it comes time for cleaning and removing castings, simply remove the locking pins and everything lifts out. It's as simple as that!