FoodChain’s Aquaponics Farm: An Intern’s Perspective

Nov 23, 2020 | Farm

By: Alex Deaton (Farm Intern)

Over a year ago I was introduced to FoodChain here in Lexington, KY. This organization is a nonprofit organization that runs an aquaponics farm inside of the Breadbox on West Sixth St. I was told that the farm is self sustaining and began to wonder how a farm could be both self sustaining and inside of a building with little to no natural light. Flash forward to October 2020, I am introduced to FoodChain once again, but this time I was given the opportunity to see and work on the farm.

The first thing I realized is that there is only one thing that is regularly put into the system to keep it going: fish food. Outside of feeding the fish the farm can be completely self-sustaining with regular check ups on the level of water, ammonia, nitrite, and nitrate. By feeding the fish you begin the cycle of nourishing the plants as well. This cycle begins with fish pooping out the food they have eaten, enriching the water they swim in with ammonia, which contains nitrogen, an essential nutrient for plants. This ammonia can be dangerous to the fish if enough of it collects in the fish tank. This is where the water system comes into play. The water rich in ammonia is drained from the fish tank into the biofilter and settling tank which removes any solids from the water that could clog the system. There are also beneficial bacteria living in these tanks that convert the ammonia into nitrite, and then into nitrate, which is a usable form of nitrogen for the plants. I learned from articles and videos that most aquaponics farms rely on pumps to move water fromI learned that there are 4 major parts of the farm at FoodChain. Each part has unique maintenance requirements. The 4 parts are the water system, plants, fish, and lights. that filters out solids and nourished plants as well as give a home to the fish on the farm

My First Day at the Farm

When I began working on FoodChain’s aquaponics farm I had a general idea of how aquaponic farms worked. I learned very quickly that upkeep and maintenance is the primary task of people in an aquaponics system. Every day at the farm there is a list of things that need to be done in order for the system to continue working properly and yield a harvest of plants and fish. FoodChain is unique by functioning inside a building with other businesses. Maintaining this farm prevents flooding as well as other issues from happening to the shared building.

On my first day working on the farm I was introduced to Kaitlyn (in person), the farm manager, and she showed me what a regular day of work is like on the farm. The first thing I was shown is draining the fish tank of solids and dirty water through the clarifiers.

The water and solids drained from the tank are then dumped into the bio-digesters. The bucket used to drain the clarifiers is put back near the drain pipes.

After that is completed the clarifier is emptied of any solids by scooping the floating solids out with a net. Sanitation is key to maintaining a clean and safe farm. After this task I made sure to wash my hands.

The next daily task is to rinse out the filter bags. These bags are placed onto pipes that pour water into a new section of the aquaponics system.

(settling tanks with filter bags attached to the pipes)

The flow goes from the fish tanks to the settling tank to the water where plants grow. These bags help stop any remaining solids from getting into the plant beds while also preventing baby tilapia from reaching the plant beds. The bags are attached to the pipes with something easily removable like a rubber band. These bags are simply removed, drained of the water in them, then rinsed inside and out with a hose, and finally reattached to the pipe. This task allows the farm to maintain a clean non clogged flow of water from tank to tank. Once again after this task it is important to wash my hands to keep a sanitary farm.

Checking the ammonia, nitrite and nitrate levels is also very important for the wellbeing of the fish and the plants. This task is performed with a kit that has very clear and easy to understand instructions.

(Water quality testing supplies)

Maintaining a low amount of algae is essential to a healthy farm. Algae in the fish tank will absorb the oxygen that would regularly be used by the fish leaving them sick which could lead to death. Checking the ammonia levels is just as important for the fish. Having too much ammonia in a system will not allow fish to extract energy from their food leaving them very lethargic. Too much ammonia over time can put fish into a coma due to a lack of energy from food. These tests are performed by collecting 5mL of water from a system of water (FoodChain has 4). Then using droppers from the kits dropping the correct amount of drops into the 5mL tubes for each chemical. The water will change into a different color after the drops have been put in. Once the color has developed using a reference page from the kit allows for you to read how much ammonia and nitrite there is in a system.

(Water quality testing supplies)

Then one of the easiest tasks on the farm is feeding the fish and shrimp. There are 6 main fish tanks with 3 smaller fish tanks and the shrimp tank. Each tank has varying sizes and numbers of fish and requires different amounts and sizes of food. The main 6 tanks are fed with larger pellets of food and the three smaller tanks use smaller pellets. The shrimp are fed with a belt feeder that feeds them at a slow consistent pace for 24 hours until needing to be rewound while food is placed evenly across the belt. Adding too much food to any tank will cause ammonia levels to increase, which can harm the fish and shrimp.

Another task to be completed is the collection of borage flowers. These are grown in a smaller “barrelponics” system which is the same as the main aquaponics system, but with all water being in barrels rather than tanks. These flowers need to be harvested every day as they bloom at random but wilt fairly soon after bloom. These are collected by cutting the flower part of the stem with some shears. These flowers are edible, and taste like cucumbers.

These are then counted and placed into a plastic container with wet napkins to keep the flowers fresh. After the container is labeled it is placed into a refrigerator for storage to later be sold.