Evolution of Aquaponics
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Volume VI, No. 1 Aquaponics Journal 1st Quarter, 2002 Evolution of Aquaponics By Scott Jones The Inca’s of Peru practiced a different style of aq- uaponics before the Conquistadors arrived. They dug Aquaponics is an intricate circular chemical oval ponds near their mountain dwellings, leaving an sequence often described, in a simple manner, island in the center. After the ponds filled, they added as, “you feed the fish, the fish feed the plants fish. Geese flew in, harvested their meals from the and the plants clean the water for the fish.” On water and relaxed on the island. Their droppings and a grand scale Mother Nature uses aquaponics 14 fish scraps quickly turned the island into a super rich, to make the world grow. Without natural aq- high quality garden. Now not only did the Inca’s have uaponics (in our ponds, streams and fields) we the geese doing the fertilizer work, they also had fresh simply could not exist here on earth. fish readily at hand and a moat around each garden to keep out hungry prowlers. Plus the mini pond/island History of Aquaponics: system created a local micro-climate that stayed a lit- Other than Mother Nature’s natural aquatic eco tle warmer than the surrounding mountains, giving systems, aquaponics first appeared at least extra days of harvest every year. The production from 1,500 years ago in China. One entrepreneur the Inca aquaponic systems fed more people per got tired of dragging feed out to the ducks, the square mile than any type of farming to this day, in finfish and the catfish. He stacked the ducks in that same type of high arid land. cages above the finfish and moved the catfish downstream from the finfish. Now when he fed the ducks their droppings and uneaten food fell into the water with the finfish. The finfish ate and “processed it.” The wastes from the finfish flowed downstream and sank to the bot- tom, giving food to the catfish which are natu- ral bottom feeders and scavengers. The proc- essed feed and anything that the catfish missed was channeled out to the fields to feed the rice crop. He fed once and harvested four times. The only drawback was that it was outdoors, so it got cold. Everything froze up for 5 months of the year. The theory was good but the exe- cution left a little to be desired. Volume VI, No. 1 Aquaponics Journal 1st Quarter, 2002 Aquaponics today: Size of the commercial aquaponic Aquaponics is back in the news today, not be- industry: cause it’s the “newest rage,” but because it The controlled environment (greenhouse) com- solves many of the vexing problems that strike mercial aquaponic industry is in its infancy, traditional soil-based growers worldwide. both in the U.S. and around the world. Cur- rently there are less than five large-scale (+1 Water is a scarce commodity. Without clean acre) facilities around the world and only two drinking water humans don’t thrive. And yet, up in the U.S. While several smaller operations to ¾ of our fresh water is used to water crops and are scattered around the country, most are on then it rapidly drains away. Not only is the the “family farm” scale, rarely exceeding ¼ farmer’s hard-earned money draining away into acre. the ground but, also, as the water drains away, it collects fertilizers and farm chemicals, leaching them into the ground water (our drinking water). The excess fertilizers and chemicals flow into our rivers and bays causing algae-blooms and killing the aquatic life. Roughly 10% of the chemicals that a soil farmer spreads on his fields are actually taken up by his plants, the rest goes on to wreak havoc on the natural life down- stream. Modern aquaponics recycles water, re- using this valuable resource. The air is also re- cycled. The fish give off carbon dioxide (CO2) as they “breathe”. The plants take in the CO2, 15 strip off the carbon (C) to build their leaves and release the remaining oxygen (O2) molecules. 10 separate aquaponic systems in the Phoenix That oxygen-rich air is filtered and then blown Foods LLC Greenhouse complex into the water for the fish to recycle. In every aquaponic system wastes in one part of the sys- tem are utilized as a resource in another part. Methods of operation: All large-scale aquaponic operations are using Pollution is drastically reduced because the water either Nutrient Film Technique (NFT) or float- and the wastes contained therein are recycled ing bed hydroponic systems combined with instead of being dumped into the ground water. either rectangular or round fish culturing tanks. The fish and plants are grown in intensive, Most small-scale aquaponic operations are us- aboveground systems. As a result, food is pro- ing the simpler Ebb & Flow hydroponic sys- duced without the loss of valuable flatlands. tems with small round fish culturing tanks. Most aquaponic growers are inside a greenhouse, so by simply adding light and heat, the grower Crops Grown...Fish: has the ideal growing season every day of the Several species of fish have been cultivated year. successfully in aquaponic systems. Current technology limits the choices to fresh-water With the aquaponic operation inside a green- species, though recent research has shown house, the need for pesticides and herbicides is promise on medium salt-water (brackish water) minimized. Cultured beneficial insects will eat species such as Hybrid Striped Bass and the occasional bug that manages to get past the shrimp. By far the largest share of the aq- walls of the greenhouse. The tightly controlled uaponic fish market, in both pounds harvested hydroponic section of the operation is naturally and number of commercial operations, goes to weed-free. Tilapia. Tilapia has several attractions for Volume VI, No. 1 Aquaponics Journal 1st Quarter, 2002 commercial operation: they have a short cycle system and the poundage of plants in order to prevent from birth to harvest (6-9 months), tolerate dras- toxicities and deficiencies of various elements from tic swings in water quality and are tolerant of low developing over time for both the fish and the plants. oxygen levels for extended times. Unfortunately, the farm-gate price, direct to wholesalers or haul- The plants used in large-scale operations must have ers, is barely above the break-even costs. Tilapia the same nutrient needs the entire way through its life is a great species with which to start a system, cycle (i.e. lettuce needs high Nitrogen (N) levels at all but a poor choice for the long-term operation of a life stages). Fruiting plants such as tomatoes and viable commercial facility. peppers need high nitrogen for good initial vine growth, then low N and a high Phosphorous (P) and For long-term economic Potassium (K) levels for good viability and to lessen the fruit development. Customized threat of catastrophic dis- commercial fish feed blends are ease loss, a mixture of not available with variable NPK species is advisable. ratios. Therefore, since it is the Prices for fish fluctuates fish feed that ultimately deter- by species. While one mines the fertilizers fed to the species is high, another is plants, only plants that thrive on low. Sudden inflow of high N levels are suitable for fish from overseas mar- commercial production with to- kets can drop a profitable day’s technology. The near fu- species of domestically ture looks to change this one- grown fish down to, at Above: Pearl tilapia step approach. Custom mini- 16 best, a break-even point in Below: basil mills and extruders, along with less than a year. Disease advanced adjustable formulas of is often species-or- feed, may soon produce cost- cultural-condition- effective feed for maximized specific. What will dev- growth of fish and plant, no mat- astate one species will ter what the stage of growth of often totally pass over a the fish and the plants. different species in the next tank. Suitable commercial crops for aquaponics that require high N Presently all commercial are greens such as lettuces, aquaponic facilities and mints, and culinary herbs. Other nearly all aquaculture fa- potential crops for commercial cilities produce food fish. production are medicinal herbs Potential new markets are likely in ornamental and plants and, also, plants grown for their essential pond fish and in aquarium fish markets, both of oils used in manufacturing and pharmacology. Holo- which are forecast to grow dramatically as more pathic medicine has seen a 30 year up-swing into people stay home and invest in their private wide-spread acceptance limited, in part, by the un- space since the events of 9-11-01. availability of fresh (as opposed to dried) plants on a year-round basis, which could be solved by green- Crops Grown...Plants: house production. New plants are discovered almost Nearly all plants can grow in an aquaponic sys- daily that have pharmacological properties but are tem but only a few have been tested and proven normally available only in small quantities and often to be economically viable. For the most efficient in far-off lands. Aquaponic greenhouse production operation of a commercial aquaponic facility, a guarantees a consistent, high quality source of the steady condition must exist between the pounds plants that the pharmacological market craves. of fish (including the relation to fish feed) in the Volume VI, No. 1 Aquaponics Journal 1st Quarter, 2002 Integration of technology: ous techniques, small plantlets can be stored Successful commercial aquaponic operations for many months and then brought to full luxu- in the future will rely in part on three major riant growth when the market is ripe.