In a relatively short amount of time you can build your own backyard aquaponics system using a intermediate bulk container as the main component. With an aquaponics system set up in your home you can not only cultivate organic vegetables and herbs, but you raise freshwater fish as well. Besides the fish food, there are no external inputs, making almost completely sustainable. There is no one way to build an aquaponics system. As long as you have the right parts set up correctly, your system will be a go. The basic idea and principle elements include a fish tank and a grow bed with a flood and drain system interlocking them.
Step 1: Cut Tank and Barrel in Half
The first step is to cut the intermediate bulk container in half horizontally. This will be the fish tank. Once complete, trim the edges by installing the irrigation pipe along the rim. This will prevent the sharp plastic edges from being a cutting hazard. Next, cut the 55-gallon barrel in half, only vertically. When laid on its side, this will make the grow bed.
Step 2: Cut a Hole for the Drain
In the halved barrel, cut a hole in the bottom for the drain pipe. This pipe should be positioned vertically in the barrel. Before sealing it in place, drill an 8mm hole in the pipe just above where it will be sealed to the barrel. Make the pipe long enough to reach the just below the level of gravel in the barrel. Surround the pipe with a larger piece of PVC with numerous 8mm holes drilled in it all around.
Step 3: Mount Barrel, Fill with Gravel
Cut two lengths of 2x4 lumber and position them atop the fish tank container. Space them apart so they will support the weight of the barrel and secure them to the rim. Atop the lumber place the barrel with the drain emptying into the tank. Fill the barrel with gravel up to a level just barely higher than the inner drain pipe.
Step 4: Install the Pump and Timer
In the fish tank install a submersible pond pump with a timer hooked up to it. You'll need an electrical power supply for this. From the pump, piping will extend up to the grow bed. Extend the piping over the grow bed so water pours over the gravel in 2 or 3 places.
Step 5: Fill Tank, Set Timer
Fill the tank with de-chlorinated water and set the timer to pump for 10 minutes and drain for 5. Once plants are growing and the nitrogen cycle is up and running, this may have to be adjusted. Carefully place a few extra plant starts in the gravel so their roots get submerged when the pump brings water in. The pump should pump fast enough to fill the grow bed and reach the overflow pipe in 10 minutes and then drain almost completely in 5 minutes.
Building your own aquaponics system is a fairly easy process that requires a lot of fine tuning. Once the fish are in the tank and the plants are growing, the nitrogen cycle will have to be optimal. A proper flood/drain cycle achieves this.