Earlier this week, I discussed why I prefer aquaponic gardening/farming over traditional techniques for most crops. I’ll keep the traditional garden for the root vegetables and tubers. I’m starting to design my new aquaponic system around vertical farming ideas. The good people at Bright Agrotech and Upstart University have published a wealth of great information on these topics.
I am considering using two 410-gallon aquaculture tanks, each with about 300 gallons of water. I should be able to raise 30-40 catfish in each tank, maybe a few more. These will be plumbed to the solids filters using a solids-lifting overflow before emptying into the sump tank.
Each tank will have its own filter, a 30-gallon barrel with a cylinder made from a 5-gallon bucket suspended near the top. The bucket forces the water coming in the side of the barrel to flow down to the bottom of the barrel before returning to the drain in the center back near the top again. There will be a second drain at the bottom for draining solids when cleaning. The plants use dissolved fish waste as nutrition…the solid waste needs to be mineralized to be useful in the aquaponic system.
The sump tank is the centerpiece of the aquaponic system. I plan to use a 330-gallon IBC tote mostly buried in the ground. Water from the fish tank flows into the sump tank after passing through the solids filter, then gets pumped back to the fish tank. A second pump carries fortified water from the sump tank to the grow pipes. Burying it allows me to let gravity move most of the water. It provides the extra benefit of helping regulate the water temperature.
Each 3-inch grow pipe measures 4 feet long with a 3/4-inch slot cut down the length. I insert a “sandwich” of two layers of filter media with the roots of the seedling/plant in between into each pipe. Each frame holds up to 30 grow pipes and each pipe holds up to 8 plants at a time, resulting in 240 plants per frame! The fortified water from the sump tank flows to the top of each grow pipe and trickles through to the bottom. At the bottom, a rain gutter collects the runoff and directs it back to the sump tank.
There are a lot more things to consider as I move forward on the design. In the picture at the top of the post, there is a framework “cube” around everything. I plan to enclose the system in a greenhouse so I can regulate temperatures and grow more produce year-round. More on that part in my next post.