Explain It Again, Please

An In-Depth Look at Aquaponics


Greener Portions is a farm. Not really in the traditional sense, but more like a recirculating farm. Recirculating farms use constantly cleaned, recycled water in place of soil as the basis to grow food. We use about 90% less water than a traditional farming operation. We are also using far less fossil fuels because we don't need machinery. Let's break down the parts of our recirculating farm in hopes we can all learn a little something. There are four essential components to our man-made ecosystem: the fish, the water, the micro-organisms, and the plants. If you think back really hard to your days in school you may recall a little something called the nitrogen cycle. Apparently, it's kind of a big deal. Something about being the building blocks of all things that grow. Anyhow, our four parts are what help create this cycle so we can grow delicious foods for Cincinnati.

The Fish

They are the engine that drives the system. We can use a number of fish to do this, but for our purposes we have decided to go with hybrid striped bass, channel catfish, and hybrid bluegill. They all grow quickly, don't mind commercial fish feed, and can survive in numerous types of water qualities and climates. They also make for great table-fare and are some of the most popular to eat. A fish secretes ammonia through its gills when breathing and out of its fish bum after digesting food. Without this source of ammonia, we can't start and maintain our cycle.

The Micro-Organisms

Beneficial bacteria are introduced into the water along with plenty of oxygen. This can be done by man (which we did) or by just waiting for Mother Nature. They will naturally appear once the fish waste is added to the water, but that can take a long time to happen on its own. These bacteria will convert the ammonia into something called nitrite. As nitrite levels build, another type of beneficial bacteria begin to appear, and those nitrites are converted into nate (nitrogen). This nitrogen is what our plants use to grow. It is worth noting that all three of these elements are toxic to fish at certain levels. Only once the water has truly cycled and plants added are they able to keep each other in check. But nitrogen isn't the only thing that our plants need to develop properly. We feed premium feed to our fish, containing a balanced blend of nutrients and minerals which are then passed along to our crops.

The Water

As you may know, fish need water to survive. But that's not the only reason water is important here. The water that flows in our grow beds and fish tank move along the previously mentioned micro-organisms and allow for the roots to uptake the nutrients. A steady flow rate of this water is also essential for the health of the entire system. Because this water is oxygenated, it also keeps the roots growing and happy.

The Plants

The plants are the final piece of the puzzle. They can only grow well if the three previous components are present and working correctly. The roots from the plant grow down from the net pot into the water which allows for uptake of nitrogen and other minerals. In doing so, it removes enough nitrate from the water that the fish remain healthy and happy. Because living in this water is essentially like living in fertilizer, our plants grow fast, very fast. It has been said that a mature aquaponics system can grow the same plant in half the time than can be done in traditional dirt farming.