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.