Oct 07

Aquaponics Global Consultancy Update


Here at Aquaponics Global Consultancy we are getting busy. At the moment we are partnering with the Green Man Solutions company based in Florida, USA to roll out some medium sized aquaponic farms there very soon, as well as doing a feasiblity study and funding drive with a church community here in London, UK for what is very possibly the first large-ish scale urban aquaponic farm and community in London, UK.

The logisitical and financial challenge of setting up urban and suburban farms, fish farming and vegetable farming right by the consumer market in these interesting times is very stimulating. A lot of the cost and funding details necessary to do this internationally have not been sufficiently well examined before, and as a result, I find myself writing the book on this with my partners here in the UK and elsewhere.

As a consultant, I am not a charity however, and charge fees for my services. This is because I am not an N.G.O. but a business person who is obliged to pay bills and so has to make a profit from my activities!
In cases like the church hall, of course I cannot charge anything until funding is acquired, but my time is nevertheless extremely valuable.  There are few qualified and experienced aquaponics professionals in the UK, and they are still thin on the ground in other parts of the world as well.

To be an aquaponic farmer, you first have to have some years of experience of ORGANIC FARMING.
Organic farming is farming as a business, not a hobby, while using no artificial fertilizers, pesticides or herbicides, antibiotics, etc. on your livestock and plants. Aquaponics is a marriage of intensive aquaculture with intensive hydroponics. You have fish in your recirculating aquaculture system as well as the plants, and so cannot use any pesticides or nitrate fertilizers because they will kill off the fish within around 30 minutes, no joke since you have thousands of fish in the aquaculture sections of these systems.

DIY aquaponics is becoming popular as a hobby, but there are still very few self-built DIY aquaponics large-scale aquaponic farm operations out there.  Aquaponics requires a static tank and pipe system of a specific, carefully calibrated plumbing and water flow rate design.  You are going to have to fit a whole riverine ecosystem in there and the aquaponics system will have to serve this ecosystem with the right dissolved oxygen, flow rates for the water, filtration parameters to keep ammonia and nitrite levels extremely low, and so on.

High ammonia and nitrite levels in your water will kill your fish very fast, as will inadequate added oxygen levels.  Intensive fish farming as here in commercial aquaponics systems requires very high levels of additional bubbled-through air in the water throughout the system at all times to supply the fish and plants with enough oxygen to keep them healthy and comfortable. You want them to grow!

Feeding your fish involves the main external input to your aquaponics system apart from water and electricity, namely, fish feed. Aquaponics fish require a measured amount of feed every day to be split up into three human person-observed meals, where you allow the fish to eat as much as they want for five to ten minutes. Overfeeding the fish, which often happens if you use an automatic feeder, will only leave uneaten food in the tanks and cause rotten food to make ammonia and nitrite levels spike, killing off thousands of your fish.

Since the cost of feedstuffs for farm livestock, including fish, is currently soaring we are, like many other fish farmers, currently looking at alternative sources for fish food, such as black soldier fly larvae farming. The most commonly farmed aquaponics fish worldwide is the tilapia fish, because it is an increasingly in-demand fish, it grows fast, and is tough and relatively human error tolerant.

Plants growing in an aquaponics system however are not so human error tolerant.  You need to be pretty expert in spotting pests that have set up home among your crops, so you know what kind of integrated biological pest management tactics to use, and when to use them., you can only use green, pesticide-free integrated pest management, usually a combination of companion planting of pest-repellent herbs and flowers next to crops, such as marigolds and garlic.

In aquaponics you can also employ the judicious use of non-toxic sprays such as bacillus thuringensis spray (not the same as when it is inserted genetically into GM crops, this is the old-fashioned method) and pH-altering anti-fungal washes of a non-systemic and non-toxic nature (usually based on potassium salts).  You need to have studied this properly for quite some time in the field.  This is one of the problems with DIY aquaponics hobby enthusiasts, pest management is often hardly considered until the pests are well established and difficult to treat.

This goes far beyond the scope of the back garden DIY aquaponics hobby into the world of intensive agriculture.  As you can see, training and experience are necessary to understand not only how to construct your DIY aquaponics commercial farm, but how to produce food intensively on a large scale aquaponic farm with fish farming and hydroponics working together.  A large aquaponic farm has aquaponics system after aquaponics system in use.

We are convinced here at Aquaponics Global that the aquaponic farm is the way forward for many farmers both in Western and developing countries, and that building costs need not be too extortionate if you use local materials and technologies wisely. However, this is not fish farming using ponds! I get a lot of requests about ponds, and we never use them. Aquaponics requires a controlled growing environment, fish farming and hydroponics in tanks of water!

In order to find out how we can help you with aquaponic farm construction and aquaponics system professional training, please do not hesitate to put in a request here:

Call me! - Charlotte Appleton: Offline

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We can work out all the details of your aquaponics project from startup costs to break-even studies, construction planning and site management.

Don’t forget to bookmark this site to be able to find our next aquaponics update!


Jul 28

Hunger And Aquaponics.

Hunger stalks the planet. There has just been massive crop failure in the grain and soy belts of North and South America,  due to drought and the failure even of ‘drought resistant’ genetically modified crops.  Climate change is seriously disturbing weather and rain patterns globally. With crop failures increasingly prevalent, hunger edges closer to us all.

Conventional agriculture, organic or GM, depends on rain and rapidly depleting underground water supplies. Fertilizer is essential and made from ever more expensive natural gas and oil feedstocks. These are also finite, will keep going up in price, and will eventually run out.  The cost of all these chemicals is eventually passed on to the consumer.

In many parts of the world, this means that basic staple foods are out of reach of the incomes of many people already. Hunger has become a normal daily experience for many. Food grown conventionally is just becoming too expensive, and conventional agriculture is just too vulnerable to the crazy weather. Food insecurity and downright hunger are now stalking everyone.
How, then, are we going to eat? While debates rage and conventional agriculture goes on with business as usual, failing due to droughts, storms, and new crop-devastating diseases immune to modern controls, hunger is increasing its grip on human populations across the globe. Conventional agriculture is proving totally unsustainable, if not downright unworkable in current climate conditions. Hunger is even making its presence known among the urban poor of so-called rich Western countries. Food prices are rising at a steady 140% year on year globally.  That includes the food prices in your local corner shop.

The answer has already been invented and is catching on.  It is totally sustainable. It does not use soil, pesticides, herbicides, artificial fertilizers, genetically modified crops or fish, or antibiotics. It wastes 90% less water than conventional agriculture, whether organic or chemicated. It does not need expensive, risky genetically modified seeds, organisms, or plants. If more generally adopted by farmers worldwide, it promises to end food insecurity for millions of people.

It is a way to raise fish and vegetables intensively in the same recirculating water.  It marries intensive fish farming and intensive hydroponics and by doing so, gets rid of the endemic problems of both technologies.  The vegetables clean the water for the fish, so there are no uncontrolled effluent discharges to the environment.  The fish fertilize the water for the vegetables, so no artificial fertilizers need be bought. Plants love this and grow up to twice as fast at up to half the spacing.

It’s part of the Blue Revolution of aquaculture-water farming-that is taking the world by storm.  It’s called AQUAPONICS.

Aquaponics farms both the fish and the vegetables sustainably. Aquaponic systems growing fish and vegetables together can be certified organic. Everything grows in tanks in  aquaponics, and water evaporation is stopped by shading the fish tanks and enclosing the water almost completely in the hydroponic raceways, so at least 90% less water wastage occurs than in conventional agriculture. Most water is constantly recycled between the fish and the vegetables.  Only around 1.5% leaves the system every day as a consequence of fish solids flushing and cleaning, and this can be scavenged back by dewatering the solids, and reused for irrigating soil crops such as orchards.

Aquaponics is a proven technology that has been used commercially since the 1970s. It also uses around 17% of the energy used by conventional farming, since no trucks, tractors, and other machinery are necessary. As a modest user of energy, it is also very suitable to be operated using alternative energy sources such as wind power or solar panels. It’s all on the spot and harvesting is easy, especially with floating raft aquaponics systems, where the rafts are lifted onto trestles and harvested at waist height in a few minutes.

Aquaponics is a way to build efficient, highly productive, sustainable, largely organic food factories. It is industrial agriculture gone green. It’s renewable food. And it fits snugly into a climate controlled greenhouse, and reduces water use on the farm by at least 90%.

It’s taking off right across the United States and Australia. Properly designed and managed aquaponics can easily produce far more food, far faster, than any form of conventional agriculture using soil. Aquaponic farming is the farming method of the present now, not just the future.

Jul 16

Drought, The Polar Ice Caps, And Aquaponics.

lettuce seedlings in the UVI aquaponics system

Lettuce seedlings in the UVI aquaponics floating raft system. 29 days from seedling to market size.

All over the world, weather patterns are being affected by record melting of the polar ice caps this summer.  This is causing drought in the United States and South America, while record rainfall in places like the UK is causing serious flooding. This is because the icy water released is altering the course of the Gulf Stream and other ocean currents that drive the weather globally.

Meanwhile, farmers are suffering from crops being lost due to this melting of the polar ice caps.  This means the price of food will go up sharply worldwide by next year or earlier without a doubt, as food supplies from last year are exhausted and not replaced from harvests that failed this year.

In conventional farming, it takes a whole season in most cases, 180 days at least, to replace a crop that has failed, and if the crop is grown in a place with a harsh winter climate, it will take a year for that crop to be replaced. So in many parts of the mid-western United States, for instance, where the winters include snow and ice, the grain crop that is currently failing will not be replaced for a year.

In aquaponics, a water-saving farming method using a mechanical aquaponics system (see image, left) which requires less than 10% of the water used by conventional farming methods, crops grow up to twice as fast at up to half the plant spacing in the rows.  This means that if a crop fails for any reason, up to twice as much food as grown in conventional farming can be grown in up to half the time. Leafy green spin

Also, droughts cannot affect an aquaponics system very badly, since it constantly recycles the water it uses, and only loses less than 10% of the water used a day to the outside, where this water is reharvested and can be used for normal soil crop irrigation.  Crops in an aquaponics system are grown in this recycled water from intensive fish farming, and the water is then returned clean to the fish to be re-used again and again.  A well designed aquaponics system actually loses only around 1.5% of the water in the system daily to the outside for re-use elsewhere.

Conventional farming loses 90% or more of water used daily to the environment.  This is why it is so vulnerable to drought. This is the same using a drip irrigation system or overhead irrigation. The water used in a drip irrigation system is only used once.  It is not recycled for re-use over and over again. Although a drip irrigation system is a good way to save water during a drought, it is not nearly as drought-proof as an aquaponic system, which, although it grows crops in a large volume of water, is specifically designed not to lose any significant amount of that water to the environment through evaporation and venting to the outside. A great many different crops including corn and pseudograins such as amaranth and quinoa can be grown very successfully in a properly managed and designed aquaponics system.  Amaranth is related to ‘Chinese spinach,’ a stir-fry vegetable.  Both the leaves and the seed heads, which require little further processing, can be eaten.

With this year on year continued massive meltdown of the polar ice caps and subsequent disturbance of weather patterns, drought and flood conditions look set to continue.  This does not bode well for the world’s food supply and all farmers need to save water and be in better control of water use generally. Also where floods are concerned they should be able to protect their crops from those, too.

With aquaponics, they do not just get crops but also useful protein, in the form of sustainably farmed fish.

By growing a much larger proportion of our food in aquaponics system tanks along with fish, which supply the nutrients for the plants free of charge, crops can be grown in controlled off-the-ground aquaponics systems. Aquaponics systems are intensive fish farms tied into intensive hydroponics systems, where the fish waste water is pumped around hydroponics systems and then back to the fish rearing tanks. No expensive fertilizers are needed. The fish make the fertilizer. It’s organic!

A short on-site training session is all that is required to turn a conventional farmer into a skilled aquaponics system farmer. Such a farmer is prepared to farm without being anything like so vulnerable financially to the weather in the form of drought and flooding.  If the funds are available, an aquaponics system can even be built inside a climate-controlled greenhouse!

Jul 14

Arduino-Based Aquaponics In a Food Desert.


This is food being grown in an aquaponics system in the middle of a concrete food desert in Oakland, California, USA.  Food and fish are growing well due to a lot of dedication and attention.

This is a clear explanation of a small aquaponics system that is almost completely automated and off-the-grid. It uses solar power. This aquaponics system talks to the farmer on his mobile phone, telling him what is going on with his fish and if his food is growing well.

However, if any of the automated sensors break, for any reason, disaster could happen to an aquaponics system, with no-one actually there to fix it.  A lot of aquaponic systems have a 30-minute time margin before massive fish deaths begin due to aeration and pumping not happening or being substantially reduced. This will happen even in an automated system. This means that if you get stuck in a traffic jam trying to get to your automated aquaponics system to fix the pump, many if not all of your fish could be dead by the time you get there. Automated systems for aquaponics are certainly attractive, but you have to realize they also have automated limitations!

If the sensors are out of action, you may arrive the next day to find a lot of dead fish and your plants wilting.

Growing media based aquaponics systems like the one in the video do not retain water in the growing media.  Inert growing media such as pea gravel and expanded clay balls, also called “clay rocks”, “hydroton”, and “hydroleca”, do not retain or store water like earth and compost do.  If the pump is out of action, in a flood and drain system, or even some constant flow systems without standpipes in the growing media filled growing beds, all the water will return to the fish tanks. Then the growing media will rapidly start to dry out.  If this is happening in hot weather, you had better get there extremely quickly!

If you like this article, the aquaponics article-packed Aquaponics Global Anthology 1 is now available to download here:

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Jun 27

Aquaponics Global Anthology 1 Now Available


Shy Clam

All the great articles from the last six months of work on Aquaponics Global are now available to download for only $10!

The Aquaponics Global Anthology 1 is now AVAILABLE!

Information, essays and ideas, how-to articles and problem-solving book links are all packed into this massive volume.

Half a year’s posts on this site (more than 30 chapters in all) have been tidied up and made available without your having to navigate all over this website.

If you are wondering about getting into aquaponics for pleasure or profit, a lot of the research has already been done for you in Aquaponics Global Anthology 1!

To download this global aquaponics volume for only $10 just click below:

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Jun 27

Aquaponics And Conventional Agriculture

Aquaponics differs in many ways from conventional agriculture and other kinds of factory farming.

I have made a chart of the differences between aquaponics and conventional agriculture:

[ws_table id=”4″]

Aquaponics is really green, and can be certified organic if the correct design and methods are used. It recycles at least 90% of the water used and uses far less space to grow far more food for far longer (all year, not just seasonally). Conventional agriculture with its use of artificial fertilizer and pesticide is not sustainable and is an envirommental disaster with long-term consequences which beggar description.

Even organic soil farming cannot compete in productivity with this marriage between intensive fish farming and ‘organic’  hydroponics. However, there are also a lot of differences between the kind of hydroponics practised in aquaponics and the usual methods and equipment used in conventional hydroponics. For instance, the piping is at least 3 inches in diameter in aquaponics to prevent clogging with fish mulm.  Also, no liquid artificial fertilizer is used in aquaponics, while, just likewith conventional agriculture, hydroponics depends on liquid artificial fertilizer entirely.

Just like conventional agriculture, hydroponics eventually vents this artificial fertilizer sludge to the water table with toxic consequences.

No toxic artificial fertilizer residue or effluent is vented to the environment in aquaponics.  The fish solids are composted into organic fish manure which can be used to fertilize field crops or sold on to gardeners. Aquaponic farming is factory farming  of fish and vegetables that recycles nearly everything and processes its own waste properly.  Fish manure is a very popular product!

Unlike other forms of factory farming, aquaponic farming does not produce any unmanageable sewage runoff.  The fish solids can also be put into an anaerobic digester with the harvesting offcuts and composted to produce methane and compost. The methane can be used to fuel a steam boiler and turbine for homemade electricity to run the pumps and air blowers of the aquaponics system.  Factory farming run off its own waste products!

No pesticides or herbicides need to be used, and energy use is minimal.  Staffing ratios on an aquaponic system are very low except for harvesting which requires minim wage piece workers, just like conventional farming, but without the back breaking work of bending.  Floating rafts can be harvested from special trestle tables at waist height!  The conveyor belt planted with vegetables in your aquaponics factory farm has floating raft sections that can be lifted out of the water and placed for harvesting at an ergonomic height.  Even the disabled can work on an aquaponic farm.

This is factory farming with a green twist.

Jun 20

Aquaponics And Green Walls

green wall

Vertical green wall construction

Ornamental green walls on buildings have got quite a bit of attention recently. I was trying to get into the Queen’s Jubilee parade recently in London when I came across one of them on Park Lane, near Marble Arch.
Of course, everything growing up the building was ornamental, not edible.
It occurred to me that there are thousands of square miles of indifferently insulated external walls on high rise buildings that could be adapted fairly cheaply to growing EDIBLE aquaponic green walls.  These could easily be watered in a cascade system recirculating water from the bottom to the top of the building, using waste water from fish rearing tanks on the roof and/or in the basement of the building.

All you would need would be a couple of low-wattage aquaculture pumps such as the Sweetwater range. This would take urban farming to a new level, installing aquaponic farms all over vertical and near-vertical surfaces all over the city.

Systems of suspended platforms similar to what are already used to clean windows on these buildings could be used to harvest the crops from the aquaponics green walls.

Climbing squash

Climbing squash

Bumper crops of vining plants such as bean varieties, including soybeans, tomatoes, peppers, melons, squash, strawberries, passionfruit, and so on could be got off these vertical  surfaces. Aquaponics marries aquaculture and hydroponics, and green walls are a form of hydroponics gone vertical, which can definitely use the waste water from fish farms for nourishment for these crops.

The rooting surface would be a thick layer of coir (coconut fibre) matting stapled under a plastic mesh. The water would be piped to cascade down the building’s sides through the coir matting, to be collected in gutters at the bottom. From there it would flow using gravity to a sump to be pumped back to the fish tanks.

The usual aquaponic filtration units would stand between the fish tanks and the vertical green walls, to collect fish solids that would otherwise cause clogging and odour problems.  The plants would take up the nitrates from the fish and the water would go back to the fish tanks clean, to be reused.

Vertical hoop houses could be installed to provide winter cover and extend the growing season on the edible green walls. In tropical urban farms on these vertices, winter protection would not be necessary.

Solar and wind energy could be used to power the pumps, based on the roof.  This can be tied into heat pumps recycling heat from inside the building, heat going to waste from air conditioners, etc, which can be used to heat and cool water and hoop house interiors.  Hoop houses can be low rise, ie vertical and only the height of the crops. They can unclip in sections from the walls to give access to the crops. The crops will be living off waste heat from the building and giving back the energy as food grown in aquaponics.  The green walls will also help to stop heat from escaping or entering the building in excessive amounts.  Urban farming in this way will also contribute to the total energy economy of a building.

runner bean

Climbing runner bean

In this way, the thick layer of coir matting and vegetation would also help insulate the inside of the building, and balcony gardens could also be part of the system.  Shade could be provided for those walking beneath as well if needed.  Marginal housing estates with little level garden space could convert themselves to thriving community vertical aquaponic urban farms. Urban farming could rescue whole areas from inner city blight.

Whole city districts might eventually be mostly covered by a layer of edible food trellis gardens apart from near the street level. Because food would be produced locally for local consumption using this method of urban farming, the costs passed on to the customer to pay for food transportation from distant farms would be eliminated.  Urban farming farms the food right next to the food consumer, and the consumer of this food does not have to pay high food prices with the cost of importing food included in the price.

This would completely change the character of cities and provide jobs maintaining the locally grown food supply for people who at present may not even be employed, with training and on the spot apprenticeships in vertical farming freely available to local people.

Aquaponics is a very flexible technology that can be adapted to all sorts of sites, as long as the biological balance between fish and plants in the system is correctly maintained.  Plant growth in aquaponics is usually much faster than in soil, so that maximum advantage can be taken of all the space under aquaponic crops.  Plant spacing is usually less as well, since plants are fed direct to the roots and do not have to stretch out root mass to find nourishment.  With some crops such as basil, it is possible to grow twice as much twice as fast, and the yields go on all year without seasonal rests.

red tilapia fish

Red Tilapia ready for sale

As far as species of fish in aquaponics are concerned for this kind of scheme, it really depends on whether your building has enough waste heat available for maintaining tropical species, or not. Tropical species of edible fish such as tilapia require constant water temperatures of 20-30 degrees C.  Trout and carp varieties, including ornamental koi carp, thrive best between 10-20 degrees C.

Tilapia grows from fish fry to plate size in 6-7 months, whereas most other species of fish take two years to reach a decent size. If your fish are also going to play an ornamental role and be visible to the public, this may also be a consideration when choosing a species to raise on your roof and/or in your basement. Of course, some species of tilapia such as Mozambique or red tilapia are ornamental cichlids as well as edible culinary fish. Tilapia species are robust and do well in aquaponics. I would recommend them at least to start with, as they are a bit more human error tolerant than say, trout and are less likely to die in protest if you make a few mistakes.

University of the Virgin Islands aquaponic system fish rearing tanks

University of the Virgin Islands aquaponic system fish rearing tanks

The aquaponics green wall possibilities are endless. It’s really up to you.

Jun 15

Aquaponics – Your Community Food Bank

By getting together with other members of your local community to exploit unused spaces such as back lots and rooftops, along with waste heat and water from buildings and also food waste from restaurants and institutions, you can build integrated aquaponics systems into your area that will serve as a permanent food bank in these hard times.

You must have seen the film clips in which desperate people sit on street corners with notices saying “Will work for food.” Well, with a community aquaponic farm in place on one or several sites, people can work for food and also for other things like valuable experience and social networking on the farm.  When your farm is finished and in full production, excess food can be sold to pay a living wage to the stalwart workers who have helped to make it all happen. You may find that the farm very rapidly outperfoms expectations as a local food bank.

Building an aquaponic system can either be a million-dollar large commercial enterprise made of state of the art technology, or it can be just as sophisticated, but built out of recycled materials garnered from skips and building sites, and friendly donations of bags of concrete and rolls of LDPE pond liner.  You will need to build tanks and these can be cobbled together successfully in a variety of ways. Aquaponics is always a stimulating design challenge, but with so many successful systems like the University of the Virgin Islands type aquaponics system already proven to work, it is better to follow their lead rather than reinventing the wheel!

If you are going to use wood in aquaponics system tank construction, you should make sure it is sound and thoroughly termite and rot proofed before it is incorporated into any tank structure.  Also be very careful about copper sulphate compounds that are routinely used for rot proofing wood.  These are lethal to fish and plants.  So any such treated wood must be painted over with a non toxic paint as well to make sure the water in the system is not contaminated with copper!  If you can, use steel pipes and galvanized heavy duty welded fence wire in tank construction rather than wood for your aquaponics system. That way you avoid your tanks rotting and breaking before you can harvest the fish inside. Wood can break your food bank!

Do not use any copper pipes or implements when doing aquaponic farming.  Copper pipes and wires may be all right inside your house, but copper is a fish farmer’s and hydroponic farmer’s nemesis. Avoid it at all costs.

Fish are very sensitive to any heavy metals and will die if their water is in continuous contact with any of them (copper, lead, silver, rusty iron, and so on). When building your aquaponic food bank, remember this is not at all just book learning. You are working with living, breathing creatures who have minds of their own.  Fish and plant wrangling can be stresssful since a food bank of this sort is also a living species bank!

Various means can be used for heating and pumping water, and for creating the energy that will run the air blowers you will need to make a success out of intensive fish and plant raising on a commercially viable scale.  One of the cheapest ways of building your own power station is to build an anaerobic digester or series of digesters.  These make methane out of farm and human waste, which is ‘cooked’ by airless fermentation inside a large concrete vessel.  The resulting methane gas can be compressed and used to fuel  boilers for hot water and steam for electric turbines.  These days self-assembly anaerobic digester kits which do not need anyone with an engineering degree can be got for reasonable prices from China.  For further details, look up ‘anaerobic digester’ on http://alibaba.com.

Anaerobic digestion also gets rid of farm waste which would otherwise create a health hazard fairly rapidly.  This makes sure that your community live food bank is not also a toxic waste dump.  Ensuring your own food security should not entail creating a stink!  You need to get off the grid with your energy supply in any case, since an aquaponics system uses modest amounts of electricity 24/7.  You do not want your food security to be impacted by enormous electric bills.

Before going ahead and raising fish, find out which fish are popular already in your area and raise those.  It will be the vegetables raised in the fish waste water that make most of your profits, since fish take anything up to two years to get to plate size. So for the first couple of years, until you start harvesting your fish tanks in succession, you will be making your living off the plants, not the fish.  The fish will be too small to eat for most of that time.

Make sure that your fish tanks are seeded in succession so that you get a harvest of fish say, once every six weeks once they start to come on line. Work out how many tanks you will need to get that harvest coming in year-round, and how many vegetable raceways you will need to balance the nitrates in the system.  This is a complex calculation and will be referred to in my next How Much Fish Can An Aquaponic Farm Raise? article.

The nature of your community and the level of its commitment to farming locally and sustainably, creating local food security, will directly affect the size and success of your community aquaponic farm. You need to establish routines and standard operating procedures and stick to them.  Your local markets for your produce and fish will also have to be weaned off imported and artificially fertilized produce bit by bit. You can also expect to see an increase in the organic waste offered to your anaerobic digesters for recycling. This is free fuel for your aquaponics system power plant.  Food security depends on energy security, so training your local community to route organic waste to your digester should be a top priority in marketing your aquaponic community live food bank to all concerned..

Because aquaponic farms, properly designed and managed, can produce up to four times more food than an equivalent conventional farm on the same area, for far less inputs, you may eventually find that you can actually feed a lot of your local community members almost entirely from the produce, fish, and other food enterprises that you local community aquaponic farm has put in place.   For the food security your own community live food bank will provide over many years to come, everyone has to make a commitment to keeping up the pace of work on the aquaponic farm.

Apr 05

Agricultural Output Crisis-Food Consumption To Double By 2050

lettuce seedlings in the UVI aquaponics system

Lettuce seedlings in the UVI aquaponics floating raft system.

Food consumption is set to double by 2050 as world population increases by 40%.  Agriculture therefore has to provide this food, there is no other way to get so much food except to grow it. Agricultural output has to double at the same rate as food consumption, or we are going to starve by the millions.

However, there is only 15% more of arable land available to be put under cultivation.  The rest of the land that is flat enough and suitable for soil farming is already in use.  How are we going to find more space to meet this rise in food consumption? How are we going to increase agricultural output rapidly enough to cope with this doubling demand?

Meanwhile, in places with large populations such as China, a lot of arable land is disappearing under new cities. All these new people have to have somewhere to live and work!  All these people need to eat. Arable land is being lost at the alarming rate of over 38,610 square miles (24.7 million acres) per year. With this shrinking farmable land area, how on earth are we going to ensure that we can meet the demand created by this doubling food consumption? Agriculture as presently practiced, even with genetically modified crops, is woefully inadequate to meet such a doubling demand. How are we going to increase agricultural output rapidly enough to cope with this doubling demand?

At the same time, the sources of artificial fertilizer, methane producers such as oil refineries and natural gas production, are becoming scarcer and much more expensive.  Look at the price of gas for your car and how this is going up.  Food consumption at present is dependent on the price of oil and gas, since farming is ‘a way to use land to grow food using oil.’ We on this site have issues with that definition of agriculture, obviously.  How are we going to increase agricultural output rapidly enough to cope with this doubling demand?

Add the price of pesticides and GM crop seed and licences to all this and you are looking at hefty bills that many farmers would rather not pay, given that the prices they can get for their crops may not justify this.  But to increase agricultural output, new technologies and farming practices must certainly be adopted.  The question is, which ones?

Then look at the water demand created by intensive soil agriculture.  We are already getting massive problems caused by irrigation. This water, used only once and then discarded, is taken from lakes and rivers. These are notoriously drying up.  Without enough water to grow the food, how are we going to cope with this doubling rate of food consumption? How are we going to increase agricultural output rapidly enough to cope with this doubling demand?

Then, on top of that, look at the crazy weather we are all getting.  London, where I live, just had a heatwave in March, and then went back to around 10 degrees centigrade.  That is not normal, and meant that a lot of farmers had trouble with crops putting on growth, and then being chilled out.  But if we are to continue depending on the weather holding off for reliable food production, we are deluding ourselves. We are in an era of acute climate change due to our own profligacy coupled with natural causes, still poorly understood.  If we cannot control the climate, how are we going to guarantee we can meet this doubling demand for food caused by rocketing food consumption?

Of course, if you live in a city, you will not notice the trouble farmers are in, what with operating costs as above, and weather freakouts as above.  In many places tornadoes, freak frosts, and floods are then followed by drought.  These are hardly optimal growing conditions.  But as a food consumer, you may well be noticing the soaring cost of your own food consumption.  What percentage of your living expenses is taken up by food costs today, and how much has that percentage grown in the last few years? Is this sustainable for your budget? How are we going to increase agricultural output rapidly enough to cope with this doubling demand, and keep food prices affordable?

Then, on top of that, add the politicians and the banks, who are playing pinochle with the economy at the moment, due to rampant greed, political corruption, and grand but impractical ideas for solving problems that are to a large extent manufactured by the very people who are purporting to solve them.  Political factions create political fictions to suit their own ends. Never forget that. But plants and animals couldn’t care less about fictions serving political ambition.  They need precise routines and conditions to thrive, above and beyond any dictates of policy.  However, economic mayhem caused by the people in charge may affect supply lines for animal feed, truck fuel, etc. and this may then impact the food supply by starving out the livestock, or bankrupting the farmer.

How is this going to ensure that we meet the demand caused by rocketing food consumption?  Well, it isn’t.  Food consumption and agriculture are badly represented in the media and hardly mentioned at all across web directories and search engines.  People take farmers for granted until their bellies are empty.  Many children now think that fish grows in fingers and milk comes out of a bottle.

Natural gas, the main feedstock for artificial fertilizer, is running out.  It is becoming increasingly expensive to obtain, and that price is passed on to the consumer, not only in his or her domestic heating and gas bills, but in the price of food. Food prices reflect the prices of everything that has gone into producing that food, however much we take farmers and their work for granted.

When the natural gas gets really expensive, so will food, unless we stop using artificial fertilizer in the massive amounts now commonly employed to grow food.  But how to get nitrate fertilizer without obtaining it from natural gas?

Actually, there is a really efficient substitute for that natural gas that is used to make artificial fertilizer and, incidentally, hydroponic nutrient fluid, which is also getting really really expensive, no surprise.

It is essentially free, and in abundant supply.  It can be created anywhere for a very small investment. No natural gas is involved or goes anywhere near it.

What is this really cheap and abundant natural fertilizer that costs hardly anything?

It’s fish farm waste water.

Fish farm waste water!!!” you say, with horror.  Isn’t that the stuff that gunges up waterways and poisons lakes? Well, yes, if you throw it out, which is what usually happens, that’s true.

However, if you retread your fish farm into tanks, not ponds, and marry your fish farm to a hydroponic vegetable farm, you can use your fish farm waste water to grow more food per hectare than any other form of agriculture known. And you can grow this food up to twice  as fast as in soil.

The waste in the water is digested and absorbed by the biofiltration process provided by the plants and beneficial bacteria in the water supply.  No waste water gets dumped into the environment.  No lakes and rivers get polluted.  The only important input is fish feed, and the only (highly controlled) waste output is organic fish manure, which can be used safely on field crops or sold to garden centers for gardeners to use.

This system uses less than 10% of the water required to grow equivalent amounts of food by conventional agriculture, including the genetically modified kind.  Most of the water gets recycled as it is pumped from the fish to the plants, and from the plants to the fish. It also uses less than 10% of the space for the equivalent amount of food, if properly managed by trained and dedicated staff.  That’s around 40% more food per hectare than soil agriculture.  Without needing any natural gas or oil-derived fertilizer or agrichemicals. The fertilizer is in the fish water.

So with aquaponic farming, you grow nearly double the amount of food, on far less space and waterYou more than double your agricultural output, while spending less on inputs and land. In fact, you don’t even need land for this kind of agriculture. You can do this in the city, on rootops and back lots. This puts land back into food production that was taken out of production by urban sprawl. And it reduces the cost of transportation of food to the markets to zero.  Also, you can use various alternative energy technologies to power the pumps, the air blowers, the grow lights, and the greenhouse heaters you may need.

Which is what you need to keep up with that doubling demand for food, that soaring rise in food consumption, those spiralling food costs. And to divorce agriculture for good from its dependency on oil and gas.

To learn more about the solution to agricultural output shortfalls, straightforward low-tech methods for growing far more food for less inputs, on far less space, (you do not even need farmland for this, you can do it on a back lot in the city, without soil in any form) there is a little book, What Is Aquaponics: Aquaponics How To, that explains the basic, inexpensive technology very clearly:

Apr 03

Aquaponics-Food Per Acre (0.5 Hectare).

lettuce growing at the aquaponics system of the University of the Virgin Islands

Intensive lettuce production in the UVI aquaponics system.

Aquaponics can potentially grow you much more food per acre than any other farming method.  However, it all depends on how well you manage and operate your aquaponic farm, and how dedicated you are to aquaponic farming.

Because you are farming in fish farm waste water, your crops are going to grow considerably faster, at higher planting densities.  But in order for this to happen, you have to look at and maintain optimum growing conditions both for plants and fish.

This is really vital.  You should make sure that your water quality and greenhouse or field temperatures are in the zone for growth, and not let up on your water testing and routine inspections of stock and equipment.  To get significant food per acre in aquaponics, you have to make sure that your growth parameters are under control, and that means strict attention to fish feeding charts, water quality control, and climate control (if you are using a greenhouse).

Since each plant species and fish species have different requirements, and work together differently, it is difficult to pontificate about this subject in general.  Each specific plant and fish type needs to be handled according to its needs, and according to your requirments for crop quality and fish size.  Different crops require different temperatures, different nitrate levels, and different care and pruning, etc. to give you maximum food per acre.  Lettuces (see chart below) are especially temperamental, and bolt if nitrate levels are too high, too low, if air temperatures are too high, etc.  Each plant type has its own personality that has to be catered for.

Biological pest control, the only kind possible in aquaponics, where you have fish growing in the same water as the vegetables, is another set of living creatures in the system that need attention and observation daily.  You want thriving populations of ladybugs (ladybirds in the UK).  This will keep down the aphids.  However, no aphids, no ladybugs.  The  likelihood of aphids completely disappearing once accidentally introduced is small, but you need to keep their numbers down and the ladybug is your critter for that.

Without adequate biological pest control, you will not get the food per acre or food per hectare that you require for your aquaponics business to succeed.

lettuce per hectare

Lettuce Production In Aquaponics

The above chart gives you some estimates for what is possible with just over a hectare (2 acres roughly) under aquaponics, just for growing lettuce.  However, to get results like the above you need to be a “black belt”  in aquaponics, with some heavy duty training and experience under your belt.  You can also get from three to seven metric tons of tilapia fish out of such a system, depending on how hard you are prepared to work on maintaining water quality for heavily stocked tanks of fish.

Lettuce does not need nearly the nitrate levels in the water that crops like say, tomatoes or peppers do.  So you do not have to stock your tanks so heavily, which is easier on the fish.  You can also control nitrate levels by controlling bacteria levels in the clarifier and filtration sections of your aquaponics system.  The more you rinse them out, the less nitrifying bacteria you will have in there, and the less the ammonia in the water will get turned into nitrate.  Don’t overdo this, because then high levels of undigested ammonia and nitrite will kill all your fish!

But then, the tilapia you are growing are also part of the food production volume per acre question.  It really depends on your local market for fish and vegetables, what you do.  However, it is more likely that you will make a profit on the vegetables that is worthwhile, rather than on the fish, which will probably just cover your operating expenses, as far as earning power goes.  Aquaponic farming makes most of its profits from the vegetables, not the fish.  But you need the fish to provide the miracle grow fertilizer for your aquaponic farming enterprise to succeed.

As you can see, there are many ins and outs for getting the water quality right for optimum growth conditions for fish and plants. To get the food per acre or food per hectare that you expect, you really need to read up on the finer details of aquaponic farming yourself.

A very good book, Aquaponics Q and A (The Answers to Your Questions About Aquaponics)
answering your questions about operating aquaponics systems commercially is now available by the doyen of commercial aquaponics, Dr. James Rakocy.

I highly recommend this as a compendium of problem-solving solutions which are also equipped with all the math and all the experience of a world-famous aquaponics professional, with a lifetime’s experience of real down-and-dirty aquaponic farming. Get the maximum food per acre or hectare possible with finely-tuned aquaponic farming!