Backyard gardeners have used hydroponics, a system that grows plants in water, since the time of Frances Bacon. But many amateur gardeners are switching to aquaponics, a combination of hydroponics and aquaculture, or the process of raising fish for food.
Hydroponics uses recycled water and its waste to feed plants, but when you add the component of fish, the fish fertilize the plants, the plants filter the water, the plants feed the fish, and the cycle is nearly a perfect circle.
Aquaponics creates this self-perpetuating circle of recycling. It combines fish farming (aquaculture) with the practice of raising plants in water 
(hydroponics). It is completely organic by nature, since instead of chemicals, the plants are fertilized by the waste of the fish. Pesticides cannot be used: if they were implemented, it would harm the fish, and interrupt the cycle.
The aquaponics setup requires a lot of equipment, but most of it can be scavenged: you need garden beds of some sort, filling them with gravel, clay, or a light- weight recycled stone. The garden beds can be trays or pans, with a piping system that connects the beds, for feeding and draining. You will also need to add a timer, so that your beds are drained on a regular basis: otherwise, as with all overwatering, the roots will drown. Aquaponics creates a system where the roots are always moist, but never overwhelmed.
Simply put, you pump the fish tank water over to the beds with tubing or piping to create a method of getting the water to the plants, drain the extra water, then pipe it back to the fish tank and start all over. Websites like Backyard Aquaponics.com have options to get you started, and full instructions.
Once you have devised your system, according to your budget and space, you need to choose a location that receives at least four to six hours of sunlight 
daily. Choose your plants and your fish wisely: tilapia, for instance, are only a warm water fish. Although tilapia breed quickly, grow fast, and can survive in fluctuating pH and temperatures, they cannot survive continuous cold. If you are in a colder climate, consider trout or perch. They can weather the extremes.
If you choose to garden only using water without harvesting fish (hydroponics), you can use goldfish to create your fertilizing cycle.
Select your plants according to your needs and palate, since the system, once in place, will continue to recycle and regrow. You can, however, pull and change the plants easily, since the roots will be only be in clay or rock. They plants also tend not to go into shock when moved, and are hardier than usual, once the system is in cycle.
You can choose from a wide array of vegetables, fruit trees, and herbs for your garden: just make sure they have similar needs for temperature and moisture.
You can also start many “root” vegetables for your garden from your own leftovers, using the base of the plant. Celery, romaine lettuce, onions, turnips and beets are prime candidates. Just set the bases in water wait a few days for the roots to sprout, and plant in your medium.
If you would like to know more about aquaponics, and a home-made system, check out Rob Torcellini’s YouTube post on aquaponics: he has worked out most of the kinks, and has had great success with his system.
Aquaponics has become a very popular cultural movement, especially in large cities that don’t have an abundance of green space and want to cut down on the carbon footprint caused by the shipping of fresh fish, vegetables, and fruit long distances. Check out your local community centers, gardening centers, and botanical gardens for more information about this vital and upcoming option.
It is another strong option to help keep our planet green.
Source: Baret News Wire