Plumbing

This photo shows how the water overflows from the fish tanks to the grow beds at the front of the shed, then flows down to the sump at the back.

Expanded clay pellets and pipes

Next the grow beds were filled with expanded clay pellets and pipes were installed to bring the water from the fish tanks to the grow beds. This pipe was fitted with adjustable taps that can help equalize the flow of water to the beds. The water exiting the grow beds gravity feeds to a sump at the back of the shed.

Grow beds

In this photo you can see the grow beds lined up on the nearly finished stand, and to the right, around the corner are the two green fish tanks, on a stand as well. The tops of the fish tanks are higher than the grow beds, so that the water from the tanks will gravity feed to the grow beds, fertilizing the plants, which clean the water for the fish. The buckets at the front are being used to wash gravel for the beds. This soon got very tedious, so we opted for expanded clay pellets, which are lighter, cleaner, and much easier to handle.

Blue drums and fish tanks

We started building the system in early March 2009, using as much recycled material as possible.
The blue drums used for the grow beds are recycled plastic drums used for transporting food. These were cut in half, end to end, and supported on a wooden frame. The green tank is a 500 litre tank (not recommended for potable water, but I didn't know that at the time) that we used for the fish - we have two of these lined up in series.