Speaking of the horticultural applications of pee...

But not my pee this time. I'm talking about the rather intriguing idea of aquaponics.

Aquaculture is the practice of growing fish as a cash crop.
Hydroponics is the practice of growing plants in a medium other than soil using a nutrient solution to provide them with the elements they'd usually pull from the soil.

Each of these practices on its own produces a harmful by-product. In aquaculture it's all the fish sewage. In hydroponics the nutrient solution is often not completely utilized and it's an expensive sometimes chemically intensive input.

Aquaponics combines the two systems to mimic a more natural polyculture where the plants clean the water and the fish provide the nutrients. In a perfectly functioning aquaponics system the only inputs are fish food, water to top off from evaporation and a minimal amount of electricity to run the pumps that circulate the water from fish to plants and back. I've seen these run from solar cells housed above the unit.

Tilapia is a common fish grown in this setup, since they're tolerant of a lot of conditions and can be fed table scraps (but they're vegetarians. awww). It's sort of like worm composting, but with fish. Feed them your scraps, scraps avoid waste stream, fish make "waste" into plant nutrients, plants make it back into human nutrients. Cool. I love neat, clean, all tied up in a pretty package ideas like this.

I realize, of course, that a perfectly functioning system is by no means an easy feat. One home experimenter wrote that hobby aquaponics is a good way to become a serial fish-killer until you get it right. Still, this whole thing makes me want a yard/greenhouse/place to experiment/even a big balcony really badly. And it's making Alli nervous that we may someday be that crazy house on the block with all sorts of abandoned experiments and lengths of plastic tubing in the back yard.

It's not my fault; I was born with an inherent need to tinker with things.

Oh and here's a link to a video of a home-made aquaponics system.