This is something that Bobby and I have talked about doing, and may one of these days give it a try. Aquaponics is basically growing your plants/veggies hydroponically, and utilizing the water for a fish tank. The dirty water from the fish tank provides fertilizer and nutrients for the plants, and then the clean and filtered water is returned to the fish tank. This is one of those ideas that can be as large or as small as you want to build it. Some tutorials show people using a 20-gallon fish tank, and others have an old swimming pool, or stock tank full of fish. Either way, it is an interesting idea of how to provide more of your own food, even in a small city lot, or where any kind of livestock or poultry is not permitted. This is just one idea, to give you the gist of how it works; and then there are bunches of tutorials on youtube , so you can go as simple or as complex as you want to do.