Sturdy wood boards are secured at the ground level, and horizontal pipes and boards connect the hoops.
Next is the construction of a frame for a fish tank and a shallower tank to be mounted above it.
We shared battery powered drills to create holes for large bolts.
A large piece of thick rubber liner will turn the lower part of the frame into a watertight container suitable for fish.
The upper tank with a similar liner will contain a layer of gravel and water plants. Water from the fish tank will be pumped up into that tank, where the plants and the bacteria living in the gravel purify the water for return circulation to the fish tank.
You can try this at home - with the guidance of skilled carpenters! The Growing Power method is not very high tech, but still requires serious skills. Fortunately there are plent of very handy people who can assemble hoop houses and aquaponics tanks.
Next steps for the house would be the addition of plastic roll-down liners that can keep the house warm enough to raise vegetables through the winter, as well as keep the worms and fish comfortable.
The Growing Power method composts food scrap and vegetable waste, then feeds the compost to worms in large industrial size bins. Worm emulsion, liquid drained from the worm bins, nourishes plants in the hoop house. See http://www.growingpower.org/ for details.
Click here for the second part of this post, more of Murray's photos of other parts of the process: compost and worm bins. And some thoughts about how NYC civic groups can learn how to produce real goods and services through sustainability initiatives like this.