The most simple definition of Aquaponics is the combination of aquaculture (raising fish) and hydroponics (the soil-less growing of plants) that grows fish and plants together in one integrated system.
The fish waste provides an organic food source for the plants, and the plants naturally filter the water for the fish. Aquaponics relies on the recycling of nutrient-rich water continuously. Gardening chores are cut down dramatically or eliminated, there is simply no need for that. So we are able to focus on the enjoyable tasks of feeding the fish and tending to and harvesting the plants.
And what can be harvested? Pretty much anything. In our greenhouse we use raft-based aquaponics system, which means that all our plants practically float on big several pools full of nutrient water. Plants are placed in holes in the raft and the roots dangle freely in the water. That creates a perfect environment for harvesting all kinds of salads in our greenhouse. Currently, 5 different types of lettuce (butterhead, summercrisp, romaine, red/green oak) are grown.