Aquaponics: Urban Solution for Organic Farming
Aquaponics, a symbiosis of pisciculture and agriculture that emerged as a soil-less organic farming model in several countries such as Palestine, Israel, Nicaragua has made its foray in Guwahati.
Touted to be a solution to the chemically over-fertilised vegetables and fruits that have flooded the city markets, aquaponics has been designed in the Institutional Biotechs Hub (IBH), an incubation centre of the Cotton University by a city-based researcher Chandrajit Nath. Dr. Saranga Ranjan Patgiru, coordinator of IBH, supported Nath in the project.
Talking about the design, Nath told G Plus that aquaponics is a combination of two different technologies -- hydroponics and aquaculture.
“Hydroponics is a method of growing plants without soil. The plants are grown in a water solvent and these are nourished using mineral nutrient solutions disseminated in the water. Aquaculture, on the other hand, is the farming of fish, crustaceans, molluscs, aquatic plants, algae, and other aquatic organisms under a controlled condition where we can monitor the growth of the aquatic organisms. Aquaponics is a combination of both,” said Nath, who has been researching on the topic for the past five years.
“We have created an artificial eco-system in which, the plants will be kept in a water solvent in a container in one hand and the fishes will be kept in a tanker on the other. Both the tank and the container will be connected with each other and the water will be circulated by using a motor. Now, when we feed the fish, it excretes in the water and if the fish is allowed to stay in the same tank, it will die. But, the fish excrete is a fertiliser for the plants. So, we circulate a part of the water from the tanker to the tanker containing the plants, where the plants through its roots will suck in the excreta and thus purify the water for the fish. We then pump the water back in tank again. This way, both the fish and plant serve each other in a symbiotic manner,” Nath explained.
There are parts and pieces of aquaponics reference in the ancient Aztec, China and Thailand, but in the modern context, it is often attributed to the various works of the New Alchemy Institute and the works of Dr. Mark McMurtry at the North Carolina State University back in 1969. McMurtry’s design has been enhanced and developed to acclimate for various weather zones.
In Nath’s model, he used Jeol fish due to its high survival instincts, but he claims that any fresh water fish can be cultivated through the design.
“The design is fit for any fresh water fish in the tropical region and also for any plant that grows in tropical region. One can even rear ornamental plants and pet fishes in the tank. In that case, glass tanks can be built. But, nothing marine though,” he said.
Nath vets his design to have a 2-3 times faster yield.
“Since the plants are getting direct nourishment without any adulteration, it shows about 2-3 times faster growth in aquaponics than it would have if grown under normal circumstances. And, there is no chemical fertiliser involved in both growing the fish and plants. So, it is completely organic,” he said.
Furthermore, there is very low maintenance cost involved, claims Nath.
“There is just a one-time cost of fixing the setup. To serve a family of four, the design can be set up at 50,000 to 60,000. After that, the only cost is feeding the fish once or twice a day and the electricity bill from running the pump are the only cost involved,” Nath said.
The design has been taken up by a group of start-up entrepreneurs named Zugantar Groups, run by three youths, Rupak Medhi, Ujjal Das and Tridib Barman which waits to be made commercially viable.
“We found that the design can be installed at the backyards of houses or in the roof tops or even inside the house as decoration. At a time when small-scale vegetation in the houses is promoted by governments of several states to raise the green quotient in the cities, Aquaponics will serve that purpose along with it, will also raise the aesthetics of the houses and also provide organic home-grown fish and vegetables and fruits,” Medhi said.