Posted this in a thread we had on gardening last year, reposting here as I'm a bit of an aquaponics fanboy

I don't have a conventional garden, I do have an aquaponics system however, growing fish and vege's together in my backyard.
Here's a pic of the actual system :

Basically a large fish tank below a grow bed for the plants, water is pumped from the tank to the grow bed, and returns to the tank through a siphon type device, the fish waste feeds the plants and
the plants clean the water, all I add is fishfood and the occasional top-up of water when evaporation takes a toll.
Here's a couple of trout we pulled out last year :

Beans and pumpkin growing :

corn and tomatoes that are growing at the moment :

Last years harvest of silver perch :

It's a great way to grow healthy food at home, this is just a small system as we have a small yard, but it can scale to any size, have even seen people running tiny ones using a normal goldfish bowl
some small system examples here
http://backyardaquaponics.com/forum/viewtopic.php?f=18&t=1617and large ones!
http://backyardaquaponics.com/forum/viewtopic.php?f=18&t=1619