Aquaponics Aquaponics, energy efficiency, and an ecosystem approach to food production
Aquaponics food factories
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Transcript of Aquaponics food factories
Aquaponics-Food Factories
Main Crops-Fish And Vegetables
The 4 main crops to be grown will be tilapia fish, romaine and leaf lettuce, cucumbers, and basil.
Romaine and leaf lettuce: 141,420–225,792/year.2706 – 4330/week, average. Some wastage is unavoidable due to quality control, hence the approximate figures. Waste foliage goes back to feed the fish, or is composted.
Beit Alpha disease resistant burpless variety cucumbers: 1ha (2 acres) under plastic which will produce 205 000 kgs per year. That is 451947 lb and 10.19 oz.
Waste foliage goes to feed the fish, or is composted.Genovese Basil: 1ha (2 acres) under plastic which will produce 80 metric tons or 80,000 kgs per year. That is 176369 lb and
12.95 oz. This is a high-quality, fast-growing, optimum priced crop. Target market: primarily city restaurants, but also supermarkets and farmers' markets.
Tilapia fish: 10,588 pounds per year in tanks in the climate-controlled warehouse greenhouse alone.
Including the further 2 ha (8 full sized commercial systems) under plastic we will produce 105,880 pounds of whole fish a year. This is about a third less, filleted, but the fish bone etc. waste can be converted via pressure cooking to frozen fish stock for wholesale sales to city restaurants, and the solids from this, composted. The fish waste WATER from the tanks is recirculated through a solids removal filtration system and the hydroponic floating raft plant troughs to fertilize crops and filter the water for the fish to re-use.
Fish and Vegetables/Kilos/Acre/Year
Year 1-4.5 acres Year 2-8.5 acres Year 3-8.5 acres Year 4-16.5 acres Year 5-16.5 acres0
100000
200000
300000
400000
500000
600000
700000
800000
LettuceBeit Alpha CucumbersBasilTilapia Fish
Earnings, courses, gross margin, crop earnings, wage costs. Food prices can vary, but wages always have to rise. This is
why it is important to factor in the courses to increase income. Since future prices are not known, this is calculated
at average present prices, which can be increased as necessary. So this is a minimum estimate. Note profit margins
increase with harvest volume.
Year 1-4.5 acres Year 2-8.5 acres Year 3-8.5 acres Year 4-16.5 acres Year 5-16.5 acres0
2000000
4000000
6000000
8000000
10000000
12000000
14000000
16000000
$ Total Earnings$ Courses EarningsGross MarginProduction $Wages
Low staffing levels, high productivity
The above chart estimates that in the first year of operation, with 36 aquaponic production units in operation occupying 4 and a half acres, we will need 3 apprentice technicians per unit. That is 108 initially unskilled workers.
In addition, 5 skilled aquaponic technicians who have done the University of the Virgin Islands or equivalent standard course and acquired some further experience will be necessary to teach and oversee proceedings.
These will be supplemented by 5 management staff, two managers (marketing and technology, pedagogy), a construction expert, a bookkeeper-secretary and a receptionist.
Five sales people will also be hired, on a very basic wage at the same level as the apprentices, plus commission to be decided.
The production workers and the technical management will have to do round the clock shifts and temporary accommodation in the form of solid, insulated yurts will be provided on site.
Solar Power: Concentrated Solar Power
Power Film solar fabric (O.E.M)
Powering Growth From The Sun The Nevada Aquaponics Project is in the heart of the Nevada
desert, but sits on top of a huge underground aquifer. To run the many pumps, air blowers for water aeration, and water heating in winter, as well as the offices, the yurt village, the on-site aquaponics school, food processing sheds, propagation greenhouse,outdoor irrigation pumps, dewatering systems for fish manure, fish breeding station, and so on, kilowatts of energy are required night and day. This is going to be very expensive if conventional electricity supply is used.
However, a combination of a small scale concentrated solar power station, which can store power for use at night as well, and rechargeable lights and thin film technology in the living quarters for running laptops, electronics, and lighting as required, would be an affordable and income generating strategy to provide free electricity forever. This can be financed from within a five year payback schedule. Excess current sold to the national grid would also help justify the existence of its own power station and flexible solar panels on the site. It's not as if the desert does not get enough sun!
Composting Vegetable, Fish, And Human Waste For Use On Tree Crops And For Heat Generation-Safe, Economical And
Odour Free I am talking about four separate processes: Composting vegetable waste from vegetable harvests. These
compost bins can be built around a pipe and heat exchanger system, and used to heat the fish tanks and greenhouses in winter, which have to be kept tropical, at a steady 26 degrees centigrade, around 70 degrees fahrenheit.
Composting fish waste from fish filleting and fish casualties. The result can be used on field crops, or sold to garden centers.
Composting human waste from sawdust flushed purpose built modern composing toilets (Loveable Loos). This is odor free, and wastes zero water. The heat generated by this process sterilizes the resulting compost thoroughly. We are in the desert and the eventual, separately composted result of this process can be used to improve soil for the timber bamboo estate barrier – see following slide.
Secondary settlement tank fermentation and dewatering of fish solids removed from the aquaponics systems. This results in saleable fish manure and fertile irrigation water for the bamboo.
Bamboo Barrier Around Property
Tropical timber bamboos (giant bamboos) grow extremely fast in desert conditions given a modicum of encouragement and sufficient irrigation. There is a steady amount of water – enough to irrigate a 100 yard wide bamboo barrier around the 90 acre property thick enough to discourage unwanted attention and visitors who might sabotage the systems. As a secondary consideration, these timber bamboos are now legal as structural members in buildings all over the United States, and some varieties have a tensile strength comparable to steel beams. So there is a market for these as building material and also as a source of wood for furniture and crafts. Moso bamboo is also used for fibreboard, and is cold hardy down to minus 20 degrees centigrade. This would reuse the water reclaimed from the fish solids in the settlement ponds, around 1.5% of the total volume circulating in the tanks, which has to be drained off.
Moso Bamboo Forest-Hardy, Fast!
Getting Off The Ground Fast And Cheaply
Not Just A Business-A Mission! We want to run these food factories not just as a business, but
as a way to teach needy farmers how to convert their land to aquaponic systems. In many parts of the world, people are starving because they do not have access to this technology. We are a consultancy for aquaponics and can be contacted via http://aquaponicsglobal.com . We help to make this technology available to farmers all over the world. We are also seeking funds to research putting this technology in old shipping containers, to be airlifted to famine-plagued regions.. It will be easy to set in motion, along with a teacher to teach the locals how to use the low water usage, solar panel equipped system to save their own lives, and educate themselves about ecology. If you can grow massive amounts of food in the desert, you can grow it anywhere!
You can't use agrichemicals-they kill the fish!
You don't need them anyway. Fish sweat ammonia through their gills, and this is converted into liquid nitrate fertilizer by naturally occurring bacteria in the oxygenated water. After passing through the solids removal system, the water goes to the hydroponic floating raft troughs, where plants supported by the floating rafts extract everything they need from the water flowing past their roots. They grow usually twice as fast at half the spacing, so you get a bumper crop of lettuce in 29 days instead of 60. All year round.
The water is cleaned of nitrates by the plants, and goes back to the fish in a pristine state. And so on, round and round, with very little wastage. The only additions needed are tiny amounts of garden lime and potash, and a little chelated iron in parts per million to ensure the plants don't go yellow and anaemic.
For pest control, you have to use friendly insects and bugs. They eat the pests, or make them so sickly they die.
Annual harvest $ income, at wholesale prices August 2011
Crop Categories0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
1800000
Romaine Lettuce/$1.52/kgLarge Tilapia Fillets/$4/kgGenovese Basil/$21/kgCucumbers/$2.58/kg
Estimated $ Staffing Costs, At Today's Minimums.
Year 1 Year 2 Year 3 Year 4 Year 50
1000000
2000000
3000000
4000000
5000000
6000000
7000000
8000000
9000000
Apprentices/18000Technicians/50000Management/50000Sales-basic/18000+%?
Far More Efficient Than Hydroponics
As you can see from the chart, the phenomenal amount of food that can be grown per acre easily outdoes soil farming. It actually even outdoes commercial hydroponics, when the system has taken a couple of months to stabilize biologically. There is still no scientific consensus of why this is so, but I would be willing to bet this is because this is nature working in an optimum environment, which is both cheaper and easier to run than an artificial chemically fed system. Nature is always so prolific when not disturbed, that she puts artificial systems to shame.
However, how much does it cost to construct such a system, and how long would it take to recoup the outlay? The answer is not in excess of 18 months...
What is aquaponics and why is it better than other farming methods?
It is widely thought that stocks of ocean fish will run out by 2050. We are also on the verge of water wars due to profligate wastage of water in agriculture and industry.
Meanwhile there is a scientifically mature, proven, sustainable, organic method of farming various species of freshwater fish in tandem with fruit and vegetables – AQUAPONICS. This produces up to 40% more food
THAN ANY OTHER FORM OF AGRICULTURE on 90% less land with 90% less water. It uses no expensive
agrichemicals at all. No artificial fertilizers are necessary. It also does not produce any toxic residues, only organic
fish manure that can be used on tree and grain crops, instead of toxic artificial fertilizer.
Costly Fertilizer and/or Artificial Fertilizer Not Needed
Fish sweat ammonia, which is transformed by naturally occurring bacteria into liquid nitrate fertilizer for the plants in the hydroponic element of the system. Artificial fertilizer is not needed. The only
input is fish feed, which can be grown in the system, with the protein element provided by a wormery using vegetable harvest waste as the composting base. The waste outputs are compost
and liquid fish manure made from the removed solids from the fish tank components. This is done using settlement tanks filled with
orchard netting, or other mechanical filtration methods, depending on the system you are using.
Artificial fertilizer, which is expensive, pollutes the water table and burns the soil, is not needed. Soil is not needed. The plants grow in
water or water combined with a growing medium such as expanded clay balls (Hydroton or Hydroleca, light and reusable).
The feedstock for artificial fertilizer, natural gas, is a finite resource and becoming more costly as it becomes more difficult to obtain.
Murray Hallam-Commercial Aquaponics-Hydroponics vs. Aquaponics in Australia
Some Fish For Aquaponics
Tilapia
Barramundi
Murray CodSleepy CodGolden Perch
Trout
Aquaponics - Crustaceans
MalaysianGiant Prawn
Blue American Crayfish
ScandinavianCrayfish
Freshwater MusselAquaculture
Freshwater Mussel Prawn Aquaculture
Some Vegetables For Aquaponics
Giant Cauliflower In Trout
Water And Hydroton Media
More French TarragonDoing Very WellOn Nothing But
Tilapia Water
Edible Morning GloryIn Raft Hydroponic
System
Lettuce In Tilapia WaterRaft Hydroponic System
Cucumber VinesIn Raft Hydroponic System
French Tarragon InRaft Hydroponic System
Equipment Required-Anglesey
Water Ageing In Fish Tank-Fresh Tapwater
Kills Fish in 30 Minutes.
Greenhouse At Cae Gwyn,
Anglesey, Aquaponic And
Hydroponic Farm-Trout,Carp And Vegetables
Seedlings in Rockwool Plugs
Solids Filter OutfallInto Trout Rearing Tank,
Cae Gwyn, Anglesey
Giant Kale And EscaroleAt Cae Gwyn, Anglesey,Growing in Trout Water
Thin Film Gutters With Net Pots Inserted
Equipment Required-University Of The Virgin Islands (Tropical)
University of the Virgin Islands
Aquaponic Tilapia andVegetable Commercial
Operation
Tilapia Grow Out TankWith Aeration System
Loose Leaf Lettuce InUVI Floating Raft System
Tilapia In TankTilapia Fry In CountingBowl
Tilapia Fingerling Grading
Grids-Quality Control
Farming Without Soil Or Pesticides-Fish And Plants Grown In The Same Recirculating Aquaculture System.
Water quality is essential in aquaculture of fish and plants
Farming fish and plants together is much more economical than running a fish farm and a hydroponic vegetable farm separately
Farming fish and plants together means no toxic fish effluent to local aquifers and rivers. Composted fish manure contained and dewatered. Sold or used.
Fish provide the nutrients for plants = no added fertilizer.
Plants clean the water for the fish = no expensive filtration
Plants grow up to twice as fast in fish water, at half the usual spacing = more harvest at twice the speed.
Fish can be farmed very intensively with plants as a biofilter = tilapia fish every six weeks after 1st 9 months
No agrichemicals can be used-kill fish = organic.
Nutrient And Water Wastage Eliminated, Zero Soil Damage, Zero Water Pollution.
Conventional farming uses 100% of available water – once.
Nutrients in water are lost to the environment causing nitrate, phosphate and salts build-ups in soil and water that burn out beneficial bacteria in the soil. The soil needs more and more fertilizer to produce the same amount of crop. Called eutrophication.
Feed ratio, domestic cattle and pigs = 2:1
Aquaponics recirculates up to 99% of water used. Up to 10% of water can be lost through evaporation and solids flushing depending on system design.
Dissolved nutrients continuously recycled by beneficial bacteria. No soil eutrophication, no fertilizer! No eutrophication of rivers. Up to 40% more biomass produced per acre than conventional farming.
Feed ratio fish = 1:1
Removed Solids Organic Fertilizer
Natural gas, the feedstock for artificial fertilizer, is set to run out and is already going up in price!
Continued use of artificial fertilizer burns out the natural fertility of the soil. More and more of it needed for the same crop yield.
Fish manure, which is semiliquid and easily packaged, can be administered as a slurry on field and fruit crops instead of artificial fertilizer and does not cause artificial fertilizer 'burn' when applied at the correct rates. Friendly bacteria content encourages normal soil fertility without year on year losses.
Does not increase humus content of soil.
Aquaponics is not hydroponics!
Hydroponics is totally dependent on expensive artificial fertilizers and chemical pest control.
Waste products of hydroponics WORSE than conventional agriculture
1 single product-vegetables. + pollution, toxic sludge.
'Organic' hydroponic fluid contains guano, from destruction of natural bird habitats. Still risky to water table as effluent. Phosphate
Aquaponics needs no artificial fertilizer or insecticides. Just biological pest control.
Aquaponics recycles nutrients and water.
Waste solids can be used as soil fertilizer
Economies of scale win over hydroponics. Intensive fish farming married to intensive vegetable production = less costs.
2 diverse products-vegetables AND fish.
Top Fish Trout species. Trout can be grown with
vegetables and soft fruit. Winter harvest slowdown because no heat. Take from one to two years to reach marketable size.
Trout need no additional heating. Water quality vital, since trout are sensitive.
High demand-whole fish easy to move. Good price and can also be smoked --££££.
Red And Nile Tilapia
Best fish for intensive aquaculture in a heated greenhouse-year round harvest of fish every 6 weeks and continuous vegetable harvest from serial sowings = ££££.
Resistant to disease and stress from crowding. Tolerate poor water quality, human error to some extent, unlike trout.
Whole fish and fillets to restaurant trade, ethnic markets. Fish leather also.
Top Crops Worldwide.
Culinary Herbs Basil Varieties-ready 4-6
weeks from germination. Serial sowings weekly produce continuous cropping.
French Tarragon-ready eight weeks from cutting insertion. Serial insertion weekly produces continuous cropping.
Parsley, chervil, chives, mint, etc....
Salad Vegetables
Lettuce Varieties-ready 29 days from germination. Serial sowings weekly produce continuous cropping year round.
Brassicas such as cabbage, broccoli, Chinese stir-fry veg.
Tomatoes - dioecious varieties grow well.
Cucumbers and squashes.
Space, Construction Requirements
1 1/8 acre system produces up to 500 metric tons of whole fish a year. ½ acre under Nelson & Pade systems- roughly the size of the Nevada warehouse interior- potentially can produce $ 3,85,556 in income a year (+ intensively spaced lettuce) overall. Plants need around 50% less space to grow per plant than normal. Suburban siting reduces transport costs since next to market. Greenhouse requirements should be computed to allow for vertical farming to maximize space use. Keder house design lightweight,insulates both ways. Desert situation excellent for sun.
Vertical space can be used to adapt less space to overall 1/8 acre surface area for 1 UVI type system, although ½ acre at least usual commercial size. This does not have to be all on the same level, adapt tubing, plumbing and hydroponic tanks to suit building shape and size. At least the Events Zone can be arbor-like.
Site solar panels and lighting correctly to maximize energy harvest and usage.
Fish tanks should be shaded.
Evaporative cooling can be used in summer to control internal greenhouse temperatures.
The UVI Aquaponics System
UVI Aquaponic System Diagrams
Solids Settlement And Removal
The UVI system soldids settlement and mineralization unit-water flows here between the fish tanks and the hydroponic part of the unit. The orchard netting in the tank on the right is used to capture fine particles of solid fish waste. The netting is rinsed out once or twice a week depending on how much mineralized
nitrate is required for crop growth. The tank in the centre of the picture is used to settle out the gross solids. These are captured by the baffles in the tank and transferred at least weekly from the conical bottom of the tank viaa pipe to an outdoor settlement pond. The resulting fish manure slurry can be used on field
or tree crops such as papaya trees.
Tilapia Grow Out Tanks
Tilapia Are Harvested From These Tanks On A Rota Every 2 Weeks.
They Go To A Depuration TankWhere They Stay 4-5 Days With No Food
To Eliminate Any Off Flavours From Intensive Farming.
Then they are harvested for immediate sale.
.
Hydroponic Troughs-Floating Raft Lettuce
Pipe From Solids Removal To Hydroponic Trough
Once solids have settled out of the water, it goes to the
hydroponic element of the system to feed plants.Now it carries only liquid nitrate fertilizer at the right
dilution for the plants to grow very fast.
Regenerating Air Blower
This electric regenerating air blower pumps air to the tubing that bubbles air through the fish tanks. There are two of these
pumps in the UVI system, but all intensive fish rearing systems need air pumped through the water or the fish will suffocate! Each pump uses 1 horsepower and is constantly
on day and night.
Setting out seedlings in net pots in floating raft
The UVI Aquaponics System
UVI Aquaponic System Yields
The aquaponics system developed at the University of the Virgin Islands produces 5 metric tons of Tilapia (oreochromis sp.) a year which is sold locally to the restaurant trade and local retailers. It
also produces romaine and leaf lettuce (1,400-2,100 cases a year) and basil (5 metric tons a year) as well as a number of other vegetable crops such as okra and cucumbers. This is without needing a controlled greenhouse environment since it is in the tropics, although the fish tanks have a securely anchored tin
shelter over them to provide shade and hurricane protection. To micromanage this continuous food production process, on 1/8 of an acre, at least two people are needed full-time with additional
help at harvest time (weekly) to process the vegetables and fish for market. A health inspected kitchen is in place to fillet the fish.
UVI Aquaponic System InputsTo achieve its staggeringly high continuous food output without excessive costs and man hours, and without unanticipated losses, micromanagement on a daily basis is necessary. Daily testing is in place to monitor water quality, PH levels, nitrate levels, oxygen levels, feed input and to initiate biological pest controls when necessary to avoid undesirable crop damage. Automatic sensors exist to do some of this but are really better suited to
hydroponics, since small variations in water quality can very rapidly kill most of your fish. All you need is for an oxygen line to clog or for the ammonia levels to go above optimum to lose 500 fish. Observation of live fish behaviour is often a much better indicator than a gauge that may be faulty. To ensure your fish grow at an optimal rate in this system you need feed inputs as follows: 19.6 kilos of feed per day for all four grow-out tanks. The
fish digest this and excrete ammonia. Ammonia is removed from the system by the beneficial bacteria and the plant crops at a rate of 1.6 grams of NH4-N/m2/day. A single half horsepower pump circulates water throughout the system. Separate regenerative
blowers provide oxygen to the fish tanks (1.5 hp) and the hydroponic vegetable raft culture tanks (1 hp). These pumps have to run 24/7, 365 days a year, or the fish and plants will die. Electricity for these comes from the grid, and costs circa 400 dollars a
month. Also there are various biological pest control stocks that may be needed. These can be
ordered in as insect eggs such as lacewings and ladybird eggs, parasitic wasps that feed on pests such as aphids and bacillus thuringensis, a caterpillar-killing bacterium that is not toxic to fish. This is simply mixed with water and sprayed on the affected crops. NO
DETERGENTS OR CHEMICALS CAN BE USED SINCE EVEN TINY AMOUNTS WILL KILL ALL YOUR FISH, WHO SHARE THE SAME WATER WITH THE PLANT CROPS.
Tilapia Production Cycle-9 Months
Trout Production Cycle-2 Years
Trout Grow Out Tank, Filter And Hydroton Biofilter
Fish Quality Control
Fry Sex Reversal, Sterilization. In trout, sterilization at the egg
stage prevents breeding in grow-out tanks
This ensures that all fish grow at the same rate to the same size, without juveniles and smaller females consuming food that will not make them reach plate size at the same time as the males.
In tilapia, tiny fry are fed special methyl testosterone feed which reverses the sex of female fish to male. All-male fish populations grow bigger and to a uniform size at the same rate. This is important when harvesting tanks on schedule
Breeding Supermales
An alternative to using chemical sex reversal, which carries a risk of environmental contamination if fish or water escape into the environment, is the use of specially bred genetic supermales as father fish of the fry. These supermales are NOT GENETICALLY MODIFIED. They are conventionally bred to have YY only rather than XY chromosomes. This ensures that 98% of their offspring are male. No chemicals are needed to populate grow out tanks with uniform fish. Fishgen Ltd at the University of Swansea in Wales are world leaders in this method.
Vegetable Quality Control Pest Control Aphids-introduce aphides colemani
Whitefly-encarsia formosa
Tropical snails-introduce sunfish
Thrips-introduce parasitic wasps,lacewings,ladybirds
Caterpillars-bacillus thuringensis
Red Spider Mite-phytoseiulus persimilis, feltiella acarisuga,amblyseius andersoni and amblyseius californicus
Generally encourage spiders of all sorts.
Below 60 degrees F at night when introducing not advisable. Optimum breeding temperatures will ensure the spread of beneficial insects and the rapid decline of pest numbers before visible damage occurs to produce.
Disease ControlPythium Fungus-remove affected plants.
Damping Off in seedlings - remove.
Oxygenate the water. Regularly clean out hydroponic tanks. Sterilize all tools regularly. Prevent unauthorized personnel in greenhouses. Ensure all visitors step through a bleach bath for their shoes. Ensure good ventilation round each plant in greenhouses. Prevention is best.
In tropical or controlled heated greenhouse conditions, introduce Malaysian giant prawns to the hydroponic tanks. They will help clean out the tanks, and are also a high value cash crop. Also if snails are a problem in the tanks sunfish LOVE to munch snails shell and all! Excess sunfish can be sold to aquarists as pets Small corydoras catfish varieties will eat most of your algae for you and can be sold off to aquarists if too numerous..
Fish Health
Brown Blood Disease Fish require oxygen in the water to
survive. In most natural situations the supply of oxygen in the water far exceeds the requirements of the fish but in tanks it is a major issue. Low dissolved oxygen levels will eventually lead to the fish consuming less food, thereby converting less into beneficial growth, being exposed to parasitic invasion, suffocation and death.
High levels of nitrite (NO2) in the tank water will enter the bloodstream of the fish through the gills and literally turn the blood a chocolate brown colour. This is methomoglobin which cannot carry oxygen. The fish just suffocate. You lose them in 30 minutes!.
BiofiltrationWhen setting up an aquaponic system, it
is essential that the beneficial bacteria that convert ammonia and nitrite in the water into NITRATE FERTILIZER for the plants have taken a good hold before introducing any fish at all.
These bacteria are naturally present in the air. To get them going in your aquaponic system, just introduce a TEASPOON OR TWO of ammonia to the water (such as can be bought for cleaning house) and let it circulate for at least four weeks. When you see algae deposits forming, introduce plant seedlings to your system, AND THEN INTRODUCE YOUR FISH.
Aquaponics Economics Fishy Business Vegetable Business
Initial costs to build the aquaponic troughs in the UVI system using concrete and forms were $12,537. However, other materials have been used effectively which cost much less. In urban situations weight and tensile strength, especially in vertical gardens, would also become important factors.
Crop Revenue ($/m2/yr)
Leaf lettuce (20/m2) 196
Romaine lettuce (16/m2)
157
Basil (16/m2) 515
Okra (3.7/m2) 15
Cantaloupe (0.17/m2)
*
Production cost for tilapia was $7.60 per kg, the break-even point (BEP) for all costs relating to the fish component. This is higher than the sale price of $5.51/kg. Production cost for lettuce was $12.27 per case of 24 heads vs. the actual sale price of $20/case. The major input costs for both products were subjected to sensitivity analysis to determine where appropriate efforts should be made to control costs. Output from this analysis is shown in Table 1. Fingerling cost of $1.23 each, which is 45% of total variable costs, is high due to their on-farm production in an experimental intensive system. A less intensive method would reduce this cost. For each 10% decrease in their cost the break-even price will decline by $0.29. A 60% reduction in fingerling cost, to $0.50 each, will lower the break-even price to $5.86/kg. Other favorable changes in the cost structure, a lower feed conversion ratio and lower feed and labor costs could make the tilapia production component profitable.
From 'Cost analysis of an aquaponic system,' Donald S. Bailey and James E. Rakocy, University of the Virgin Islands Agriculture Experiment Station.
Aquaponics Economics 2An outdoor aquaponic system was developed for the annual production of 3.1 MT of red tilapia
and 43,700 heads of leaf lettuce. Tilapia are grown intensively in tanks from which effluent
flows into settling and filter tanks for solids removal and then into a hydroponic vegetable
growing area. The hydroponic beds are used to grow lettuce and serve as biofilters for ammonia
and nitrite removal. High quality water from the hydroponic beds flows back to the fish rearing
tanks. The hydroponic beds are a revenue generating component of the culture system that
enhances the cash flow and profitability of the enterprise. Previous economic research found
that a farm having 24 production units had an internal rate of return of 21.7% on sales revenues
of $1,282,936 and expenses of $1,004,898 annually over a 20 year period. This was deemed an
acceptable return in relation to other investment opportunities. (Bailey/Rakocy, UVI)
Tilapia Production Component Lettuce Production Component Δ BEP ($)
Δ BEP ($)
Fingerlings ($ each) .29 Lettuce seedlings ($ each) .19
Feed conversion ratio .11 Harvest (% marketable) 1.13
Feed ($ kg) .11 Packing boxes ($ each) .21
Management Labor ($ year) .07 Management Labor ($ year) .06
Hired labor ($ year) .04 Hired labor ($ year) .55
Fish Stocking DensitiesStocking densities for aquaponics are not the same as for aquaculture. The latter has a focus on
producing fish and fish alone. Aquaponics focuses on producing fish AND crops.
The determining factors with stocking density for aquaponics are several, some of which have already been mentioned, but of which water quality is the most vital. This will dictate how many fish can be stocked in the tank and the most important factor is oxygen carrying capacity, particularly for
cooler water fish such as trout. Warm water fish such as tilapia are a tad more tolerant of lower oxygen levels, and can therefore be stocked more intensively.
Internet sources such as Backyard Aquaponics mention stocking densities of 6:1:2 - 6 kilos of fish to 100 litres of water to 200 litres of hydroponic or growing media bed. Others quote 1 fish to 1 gallon of
water. However, the practicalities are somewhat different. The higher the concentration of fish, the more feed is needed to get them to grow and the higher the levels of ammonia, nitrite and nitrate will
be. This will need very close control to keep the tank environment viable for the fish. Some fish become quite aggressive when the stocking density is low but are less so when in a crowded
environment.An example of this is the tilapia fish. These can be stocked virtually shoulder to shoulder and survive
quite well, but they are in grow-out tanks for a shorter time than trout-six to nine months for tilapia compared to one to two years for trout. Intensively stocked tilapia need a lot of attention to avoid
oxygen starvation, brown blood disease, etc.Another factor is that the fish will grow and take up more space, so 500 fingerlings are fine in a 600 gallon tank, but as they grow they will need to be split up between larger and larger tanks. The best
advice is to run under the above mathematical ratios. This will give you some room to manoevre should problems arise, such as a mechanical fault in pumps, or an energy blackout on a hot (or cold) day causing temperatures to rise or fall below the tolerance levels of your fish and causing ammonia
levels to rise to toxic levels. Add the lack of oxygen in the water and the fish will start to die very fast.
Feeding Your Fish SustainablyIt is pertinent to mention feeding at this point when looking at stocking densities. Once again we are looking at formulae here. It is suggested that fish are fed roughly 1% of their body weight each day, although this can vary up to 3% with some fast growing species. However, it is unwise to work out
how much weight in fish there is in a tank, find the correct percentage and then just chuck that amount of feed straight in. Feeding is best done on the basis of little but often. This way the fish can be seen feeding and when they are slow to come to the food it will give some indication that things should be slowed down or a problem exists with the water or health. The latter point reinforces the view that automatic feeders are fine, but like automatic dosers in hydroponics, they take away the
'hands on' approach to management of plants or fish. A breakdown in the automatic feeder will also leave the stock unfed and this can cause problems.
Quality and variety of feed is important and very careful reading of fish food constituents should be noted. A lot of commercial fish feed contains fish meal, sourced from ocean fish, which is contra-indicated when you are farming fish sustainably with a view to helping to save the oceans! For
fingerlings a small-grained food will be necessary until they reach a larger size when they can be moved up to a higher protein feed. They can go on to even larger feed as they put on weight. In addition most fish like to eat worms and bugs and anything they would hunt in the wild. Slug and
snail eggs, woodlice, mealworms etc. all disappear once tossed in the tank. If the fish are herbivores such as carp, then they will eat roots and leaves. Duckweed, which can be grown in the hydroponic
component of the system, is much loved by the omnivorous tilapia fish. Finally, if buying fish food in bulk, approach a reputable supplier, and make sure the fish is stored out
of reach of vermin such as rats. Keep an eye on the recommended storage time. Again, make sure the protein component of your fish food is not sourced from the sea!
Vertical Farming
Vertical Farming In London'Imagine a high-rise building in the heart of a city with floor after floor of vegetables and grains. There might be poultry and
fish too, maybe even a shrimp farm, providing every food that a city dweller might want. This is the idea behind vertical farms, sometimes called farmscrapers, and several cities have confirmed their ambitions to make them a reality, including
the eco-city planned for Abu Dhabi and Incheon, in South Korea.
You grow in a controlled, small-scale way on a vertical farm, so need less fossil fuel than the fertiliser and farm machinery-dependent methods of modern agriculture. Plus, as its creator, Professor Dickson Despommier, of Columbia University,
New York, points out, it's a way of getting around the farmer's number one enemy: the weather. According to DIespommier's plans, one vertical farm, rising up to 30 storeys, could provide enough food for 10,000 people.
Plants could be grown hydroponically with their roots submerged in water. This reduces the weight on the building's floors as the volume of water needed is less than the volume of soil. Chickens could be reared organically, although they would
never be free-range.
If it all sounds too much like factory farming, city-style, remember, says Despommier, that producing food in urban areas enables us to give land back to nature. “Instead of farms taking up our open spaces, we can go back to having forests
soaking up CO2 and reverse deforestation.”
The building's carbon footprint would be kept down with LED low-energy lighting, an irrigation system that recycles grey water, and lots of daylight, maximised by it being made entirely of glass. Renewable resources would be used for energy,
depending on what is available: it might be solar in a sunny city, geothermal elsewhere.
“You'd have to be clever about the design, putting plants that tolerate shade in the building's internal space and those that need more light on the outside,” Despommier says. “The first one might not be perfect, but we'd improve things each time.”'
From The Times,June 28, 2008Can city dwellers be more self-sufficient?
Why not vertical aquaponics?Mostly, when people envision vertical urban farming, they think of hydroponics in new buildings. This is both very expensive
and ecologically unsustainable, as I have explained earlier in this overview. However, all you have to do to find space for vertical farming using aquaponics technology is to look up. There is unused roof space all over the city.
You don't need to employ an architect to build your vertical farm, just take over a roof and turn it into a greenhouse, with at least one eighth of an acre of surface area including the fish tanks and the growing troughs for the vegetables. Essentially, aquaponics is really a plumbing system with fish and plants growing in it, so it can be adapted to any configuration of space with a little imagination and know how. Anything hydroponics can do, aquaponics can do more efficiently and cheaply. And
without producing the toxic sludge hydroponics does.
Since there are now low energy grow lights (yes, the ones beloved of the cannabis growing fraternity) you do not even need sunlight to start your aquaponic farm). I personally grow fruit, herbs and flowers on the top floor of my current home with the
aid of two 125 watt grow lights suspended from the ceiling, and the aquarium water from 10 pet tropical fish! I am still waiting for the solar panel to arrive, but when it does, the heating and 6 watt pumps for the tanks will run off a 120 watt solar
powered battery.
This is infinitely scalable, and what can be done in my office can be done anywhere.
There are even possibilities for restaurants to grow some of their own fish and vegetables on the premises, as part of the ambient decor. Beans and climbing vines such as passion fruit vines can be trained up trellises, grow beds can be
attractively arranged to present tomatoes and lettuces ornamentally as they grow, okra is a hibiscus variety and the flowers are very attractive, strawberries can cascade down the walls, melons , cucumbers and colourful squash of all kinds can be
trained over frameworks, you can even grow papayas and pineapples... the possibilities are endless. There is now an insulated lightweight version of the greenhouse called a Keder house, that overcomes the weight
restrictions for roof constructiosn and can be erected on rails to fold back in the summer.... In winter, you will still be producing crops and fish when farms are fallow and cold. There are no seasons in a heated greenhouse so you just go on.
Last but not least, we are all concerned no doubt about the fate of the oceans. If most of the fish and crustaceans that we eat came out of aquaponic systems, we would not need to fish the oceans. If most of our exotic vegetables and fruit were
grown in the fish water in these systems, we would not need to import them at vast cost both to our pockets and the ecosystems of the world, Food grows FAST with aquaponics. Plant roots grow downwards not laterally so plants can be
much closer together and take up less space for more. At present, if we stopped importing food, we would starve in 2 weeks!
Keder Lightweight Steel Framed Greenhouse-Bubblewrap for Aquaponics
Aquaponics Greenhouse Using Heat Pump
Grow Out Tanks-Harvest Every 6 Weeks
Grading Juvenile Red Tilapia. Note the tanks and pipework.
Cleaning The Orchard Netting Filter
Nelson & Pade System
Seed Propagation Greenhouse
Nelson & Pade Grow Troughs
Seedlings
Seedlings are started in rock wool plugs
Tilapia Fry
Carp Grow Out Tank, Anglesey
The carp grow out tank at Cae Gwyn, Anglesey, Wales produces edible carp and watercress both in the tank and in
media beds nearby. The market for carp is mostly Polish immigrants and the ethnic population. No heat required.
Netting prevents hawks from stealing the fish.
Solids Mineralization And Filtration
5 Metric Tons Of Tilapia In Tanks
These tanks at UVI produce 5 metric tons of tilapia a year in a rota system. The tilapia is harvested tank by tank and so has to be seeded in the juvenile tanks on the same rota and grown out at a uniform rate. This is achieved by making sure all the tilapia are male. The round tanks are more or less self cleaning due to water flow removing solids from curved
surfaces better than flat ones or sharply angled ones.
Fish Feeding Frenzy
The Perfect Lettuce
Easy Pick Aquaponic Lettuce
Floating Raft Culture-Food Conveyor Belt From Seedling To Harvest
Hydroton Growing Media With Trout Water
Giant Metre Wide Cauliflower
UVI Lettuce In Tilapia Water
Bibliography-Sources.Photos and videos by the author, 2010.
Cost analysis of an aquaponic system, Bailey and Rakocy, University of the Virgin Islands Agricultural Experimental Station.
An Introduction to setting up and running a hydroponic and aquaponic unit, by Rowena and Philip Mansfield, Cae Gwyn, Carmel, Llanerchymedd, Isle of Anglesey, LL71 7DD
Aquaponics, The Biofilter That Generates Income, Donald S. Bailey, James E. Rakocy, R. Charlie Schultz and Jason J. Danaher, University of the Virgin Islands Agricultural Experimental Station
Presentation © R.C.APPLETON 2011
Economic Analysis Of A Commercial-Scale Aquaponics System For The Production Of Tilapia And Lettuce by Donald S. Bailey, James E. Rakocy, William M. Cole and Kurt A. Shultz, University of the Virgin Islands Agricultural Experimental Station.
From The Times, June 28, 2008-Can city dwellers be more self-sufficient?
http://www.ams.usda.gov/mnreports/fvdorganic.pdf-Up To date wholesale vegetable prices in the USA.
http://a-c-s.confex.com/crops/wc2006/techprogram/P18855.HTM
- Eutrophication further details.
Local Nevada pricing research by Tom O'Donnell, M.B.A.
Production figures from the Nelson & Pade company website, http://aquaponics.com.
Wages calculated at slightly above the minimum current legal wage for Nevada.