4. 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.
18. 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.
19. 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.
21. Some Fish For Aquaponics Tilapia Barramundi Murray Cod Sleepy Cod Golden Perch Trout
22. Aquaponics - Crustaceans Malaysian Giant Prawn Blue American Crayfish Scandinavian Crayfish Freshwater Mussel Aquaculture Freshwater Mussel Prawn Aquaculture
23. Some Vegetables For Aquaponics Giant Cauliflower In Trout Water And Hydroton Media More French Tarragon Doing Very Well On Nothing But Tilapia Water Edible Morning Glory In Raft Hydroponic System Lettuce In Tilapia Water Raft Hydroponic System Cucumber Vines In Raft Hydroponic System French Tarragon In Raft Hydroponic System
24. 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 Outfall Into Trout Rearing Tank, Cae Gwyn, Anglesey Giant Kale And Escarole At Cae Gwyn, Anglesey, Growing in Trout Water Thin Film Gutters With Net Pots Inserted
25. Equipment Required-University Of The Virgin Islands (Tropical) University of the Virgin Islands Aquaponic Tilapia and Vegetable Commercial Operation Tilapia Grow Out Tank With Aeration System Loose Leaf Lettuce In UVI Floating Raft System Tilapia In Tank Tilapia Fry In Counting Bowl Tilapia Fingerling Grading Grids-Quality Control
35. 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.
36. Tilapia Grow Out Tanks Tilapia Are Harvested From These Tanks On A Rota Every 2 Weeks. They Go To A Depuration Tank Where They Stay 4-5 Days With No Food To Eliminate Any Off Flavours From Intensive Farming. Then they are harvested for immediate sale. .
38. 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.
39. 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.
42. 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.
43. UVI Aquaponic System Inputs To 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.
51. Aquaponics Economics 2 An 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)
52. Fish Stocking Densities Stocking 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.
53. Feeding Your Fish Sustainably It 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!
55. 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, 2008 Can city dwellers be more self-sufficient?
56. 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!
67. 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.
69. 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.