Aquaponics is an old idea that has been creeping its way into the food system all over the world. It is a blending of aquaculture, the raising of aquatic animals, and hydroponics, the growth of terrestrial plants in a liquid. The elegance of the system is the symbiosis of the animals, plants and bacteria to maximize the utilization of resources. The idea is that one feeds the other and so on to minimize inputs.
A summery of the process goes as follows: the fish in the system are feed by the farmer. In response, the fish poop, which is full of under utilized nutrients. Natural and ubiquitous bacteria grow and feed on the waste to produce other byproducts. Plants uptake this waste via their roots, which is really liquid fertilizer, utilizing the byproducts from the fish and the bacteria to grow and produce food for the farmer. The filtered water is then return to the fish cleaner and relatively free of waste produces.
Anyone familiar with recirculating aquarium system, i.e. any home aquarium, know that a biofilter is used to filter out wastes produced by the fish. These filters have to be cleaned and replaced periodically. In an aquaponics system, the hydroponic bed containing the plants act as the biofilter that produces a useful byproduct. Taken to the extreme that byproduct could ideally turn a profit.
I just came back from an aquaponics course at the University of the Virgin Islands in St. Croix. Dr. James Rakocy had been perfecting this system to the point of commercial viability for the past 30 years. He partially came out retirement to help teach the class. The university has patronized this course the past couple of years and will continue to do so in the coming years if anyone is interested.
I am no stranger to aquaculture or aquaponics. I used to work at the University of Miami's Experimental Hatchery and have been running a small aquaponic system at my house for a little over a year now. However, the things I learned help to fill in the gaps. Small systems practically run themselves, if you know anything about fish and/or plants. But, the finer details concerning water quality, design of larger systems and the business aspects have alluded me, until now.
Some people claim that aquaponics is new and it will feed the world. Both claims are false. For thousands of years, people in Asia have been doing this as they grew fish in their flooded rice patties. The fish would feed on insects and algae in the water while fertilizing the rice. The Aztecs built rafts out of lashed together wood and floated plants over lakes to produce food. No doubt that if one were to go back through history, other examples could be found; humans can be creative devils. Aquaponics has great potential, but it will be limited to supplementing the food supply for now. The world runs on carbohydrates and all the present models of aquaponics is used to grow fruits and vegetables in addition to protein from the fish. Unless the rice patty model or a large system to grow wheat or other grains can be used, not too many carbs come out of the system.
In the U.S., don't expect a large scale system to pop up next to you in the near future either. The up front costs to a commercial scale production system is prohibitive. It simply cannot compete with cheaper soil based production. The use of aquaponics will remain in niche markets for now. Small systems will be used in schools to teach and in homes to supplement food supply. The developing nations are where potential really exists for the millionaire/billionaire investors to actually built a large system.
My home system used things I could recycle when possible. The bottom tank holding the fish is an old sink from my landlord's remodeling episode. And the upper tank for the plants is a five gallon water bottle cut in half. I cheated and bought a fountain pump and tubing from Home Depot to circulate the water.
My system was not optimized for any type of growth as prescribed by UVI. When I first built it, I knew little to nothing about the factors involved, but now I could step up to a garage or greenhouse size. My little system taught me about water quality and nutrients needed for success.
A summery of the process goes as follows: the fish in the system are feed by the farmer. In response, the fish poop, which is full of under utilized nutrients. Natural and ubiquitous bacteria grow and feed on the waste to produce other byproducts. Plants uptake this waste via their roots, which is really liquid fertilizer, utilizing the byproducts from the fish and the bacteria to grow and produce food for the farmer. The filtered water is then return to the fish cleaner and relatively free of waste produces.
Anyone familiar with recirculating aquarium system, i.e. any home aquarium, know that a biofilter is used to filter out wastes produced by the fish. These filters have to be cleaned and replaced periodically. In an aquaponics system, the hydroponic bed containing the plants act as the biofilter that produces a useful byproduct. Taken to the extreme that byproduct could ideally turn a profit.
I just came back from an aquaponics course at the University of the Virgin Islands in St. Croix. Dr. James Rakocy had been perfecting this system to the point of commercial viability for the past 30 years. He partially came out retirement to help teach the class. The university has patronized this course the past couple of years and will continue to do so in the coming years if anyone is interested.
I am no stranger to aquaculture or aquaponics. I used to work at the University of Miami's Experimental Hatchery and have been running a small aquaponic system at my house for a little over a year now. However, the things I learned help to fill in the gaps. Small systems practically run themselves, if you know anything about fish and/or plants. But, the finer details concerning water quality, design of larger systems and the business aspects have alluded me, until now.
Some people claim that aquaponics is new and it will feed the world. Both claims are false. For thousands of years, people in Asia have been doing this as they grew fish in their flooded rice patties. The fish would feed on insects and algae in the water while fertilizing the rice. The Aztecs built rafts out of lashed together wood and floated plants over lakes to produce food. No doubt that if one were to go back through history, other examples could be found; humans can be creative devils. Aquaponics has great potential, but it will be limited to supplementing the food supply for now. The world runs on carbohydrates and all the present models of aquaponics is used to grow fruits and vegetables in addition to protein from the fish. Unless the rice patty model or a large system to grow wheat or other grains can be used, not too many carbs come out of the system.
In the U.S., don't expect a large scale system to pop up next to you in the near future either. The up front costs to a commercial scale production system is prohibitive. It simply cannot compete with cheaper soil based production. The use of aquaponics will remain in niche markets for now. Small systems will be used in schools to teach and in homes to supplement food supply. The developing nations are where potential really exists for the millionaire/billionaire investors to actually built a large system.
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| My home system in the beginning |
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| Lettuce, bamboo and mangroves are now growing |
My system was not optimized for any type of growth as prescribed by UVI. When I first built it, I knew little to nothing about the factors involved, but now I could step up to a garage or greenhouse size. My little system taught me about water quality and nutrients needed for success.
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