Principles Aquaponics

 

Aquaponics: How Does it Work?

Aquaponics is seen as a highly efficient farming solution that addresses these multiple farming challenges. By using less water compared to conventional farming, reducing the need for synthetic fertilizers, and minimizing waste, aquaponics presents a promise for producing food without damaging our environment.

What is Aquaponics?

Aquaponics is a sustainable farming method that combines aquaculture (the cultivation of aquatic organisms like fish) with hydroponics (the growing of plants in nutrient-rich water without soil). This combination creates biological processes that occur in both systems to create a closed-loop environment where fish and plants thrive together.

How Does Aquaponics Work?

In aquaponics, the plants are grown in the grow bed, and fish are placed in the fish tank. The nutrient-rich water from the fish tank that contains fish waste is fed to the grow bed, where billions of naturally occurring beneficial bacteria break the ammonia down into nitrites and then into nitrates. 

Plants absorb these nitrates and other nutrients to help them grow. The plant's roots clean and filter the water before it flows back into the fish tank for the fish to live. The fresh, clean, and oxygenated water recirculates back to the fish tank, where the cycle will begin again.

The Nitrogen Cycle

• In aquaponics, the nitrogen cycle is a fundamental process that transforms toxic ammonia from fish waste into less harmful nitrates. Fish excretes ammonia that accumulates in the water. Beneficial bacteria, specifically Nitrosomonas, convert ammonia into nitrites. Another type of beneficial bacteria, Nitrobacter, then converts nitrites into nitrates that serve as a valuable nutrient source for plants.
• Role of Beneficial Bacteria in Converting Waste: The presence of beneficial bacteria is essential for the nitrogen cycle to function. These bacteria colonize the surfaces of the grow beds and grow media, providing a substrate for their growth. Without these bacteria, the toxic ammonia produced by fish waste would accumulate and harm the fish. This is why the conversion of ammonia and nitrites into nitrates is essential to the aquaponics systems.

Fish and Plant Symbiosis

• Fish Waste as a Nutrient Source: Fish excrete waste that contains ammonia, a nitrogen-rich compound. Excessive ammonia levels can be harmful to fish, but this waste becomes a valuable resource for plant growth in aquaponics.
• Nutrient Absorption by Plants: As water from the fish tanks flows into the grow beds or PVC pipes plants absorb the nitrates through their root systems. These nitrates provide essential nutrients like nitrogen and phosphorus that promotes plant growth and development.
• Purified Water Returning to the Fish Tanks: The plants' uptake of nutrients fuels their growth and naturally filters the water. Purified water, now clean of excessive nitrates and other waste, is then recirculated back into the fish tanks, creating a closed-loop system.

The History of Aquaponics

Aquaponics can be traced back to the Aztec Indians around 1000 AD, who grew plants on rafts on the surface of Lake Texcoco. While the Aztec chinampas in Mexico are believed to be the basis of modern aquaponics, the people from eastern Asia (China, Indonesia, and Thailand) were also thought to be among the earliest aquaponics practitioners.

In Asia, farming involved growing rice in paddy rice fields with the help of fish such as catfish. The wastewater from the catfish tanks was used to fertilize the rice fields and other crops.

Conclusion

Learning about aquaponics can be challenging. But, aquaponics has the potential to revolutionize modern agriculture by addressing key challenges and inefficiencies in traditional farming methods. 

Compiled by: Arjun, Data Scientist