For the past four years, I have been dreaming, researching, planning, and preparing for the construction of a four season aquaponics greenhouse. The primary dilemma was that the land I had to work with was a basically the side of a mountain. The agrarian life is demanding even in the most ideal environments but at 6,800 feet above see level, the base of Pikes Peak offers a challenge to gardening that borders the realm of the inconceivable and absolute insanity.
The task began with clearing the land, constructing a series of retaining walls, and hauling buckets of backfill to create enough flat ground to perch a humble 16′ x 18′ year round fresh food factory.
The foundation is built using stacked 4″x 6″ landscaping timbers which were secured to the ground with rebar and concrete.
The floor was dug down 2 ‘ and perforated black drain pipe was laid down to be used as a thermal battery and 12 tons of gravel was hauled in with 5 gallon buckets to cover the entire footprint of the greenhouse.
The view of the foundation is looking down from a deck. at the bottom of the picture you can see the pond and aquaponics system that served as my aquaponics learning lab for two years before committing to an aquaponics greenhouse.
The framing was all done using 2×6 lumber. I would have preferred steel framing but the cost was prohibitive. The roofing and front wall are covered in 10mm thick, twin walled polycarbonate panels.
The greenhouse incorporates both soil and aquaponics as a growing medium. The front of the greenhouse has a u shaped raised bed that was built with corrugated steel panels that are 24″ deep and 30″ wide. Vermicompost buckets have been evenly spaced and buried to allow regular feeding of worms that help to keep the soil aerated and fertilized.
There are three IBC tanks that serve as the fish tanks and a 3’x10′ growing bed built on top of the tanks. The aquaponics system is an ebb and flow system that is activated by a bell siphon that drains into the center tank. Water is evenly distributed between the three tanks using a u-siphon which has proven to be functional and reliable. I really like the flexibility of the system. It allows me to keep fish and water in the three tanks isolated if need be, or they can be interconnected through the u-siphons. My original plan was to use one tank to raise minnows and duckweed as food for the fish in the other two tanks but that idea has been abandoned for three tanks filled with edible fish instead.
Heat for the greenhouse is generated by three thermal battery sources: 1. the three main fish tanks, 2. 8 black steel barrels filled with water along the back wall and, 3. a 6″ duct fan which moves the hot air from the peak of the greenhouse into the black perforated pipes that run below ground.
So far the plants in the soil grow beds have been growing well and producing a consistent supply of tasty food. The aquaponics system has taken some patience to cycle the water and build the necessary bacteria needed for consistent productivity. I currently have 20 fingerling wiper in one tank, 16 Tilapia and a catfish in the second tank, and twenty perch with another catfish in the third tank.
Special thanks to my Dad, Jim White, who came From Florida to share his 30+ years of building experience and his time.