Aquaponics – Grønn vekst

Funded by Nordisk Atlantsamarbejde (NORA)

2011-2012

Project No 510-072

Final report from the project September 2012

Stefania K. Karlsdottir, Islensk Matorka ehf., project coordinator

Jan Morten Homme, Feedback Aquaculture

Rannveig Bjornsdottir, Matis ohf. & University of Akureyri

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Table of Contents

1. Project aims. .................................................................................................................. 3

2. Project summary ............................................................................................................ 3

3. Aquaponics – the green growth of the future .................................................................. 3

4. Implementation of aquaponics in the Nordic countries .................................................... 6

4.1 Implementation of aquaponics in Iceland ..................................................................... 7

Implementation at Matorka’s production site ................................................................... 8

4.2 Implementation of an aquaponics in Norway ...............................................................13

Implementation of an aquaponics pilot plant and a research facility in Norway ..............16

5. Conclusions and suggestions for future work and Nordic collaboration .........................29

6. References ....................................................................................................................30

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1. Project aims

The project aims were to implement aquaponics in the Nordic countries, and to establish a Nordic network within this field. The work involved a common initiative in Norway and Iceland, with technology transfer from Canada and elsewhere.

Aquaponics combines aquaculture and horticulture through the use of nutrient rich waste water from aquaculture to the production of vegetables in aquaponics. This will result in minimal environmental effects of waste water from aquaculture and utilization of nutrients for the production of high quality products, thereby creating a natural circulation where waste water from aquaculture production is transformed to valuable raw materials for another production.

2. Project summary

Based on the results from the project aquaponics pilot plants have been designed and partly constructed through technology implementation in Iceland (R&D and test facilities at Matorka´s aquaculture production site) and in Norway (Aquaponics AS and R&D facility at Bioforsk). In the project equipment’s and materials needed have been listed and the most economical plants have been selected based on market value, climate and cost of production. Nordic aquaponics network has been established and is now active within the Nordic countries, with the main focus on implementing aquaponics in the Nordic countries for demonstrating the possibilities in expanding this technology. Cooperation with Canada and various other international actors has been established and is active through the Nordic network on aquaponics.

3. Aquaponics – the green growth of the future

Aquaponics combines hydroponics with raising aquatic animals in a symbiotic, Recirculating Aquaculture Systems (RAS). Aquaculture is the culturing of aquatic plants and animals, whereas hydroponics is simply growing plants in water and nutrient rich solutions without soil. The solution is created by supplying the correct nutrients plants need with water which is fed directly to the plant root base. In aquaculture using RAS, the water quickly becomes nutrient rich due to the fish digesting and excreting their food. This provides the plants with ideal water and nutrient ratios and optimum conditions for growth. The waste water is usually filtered and/or disposed off in order to keep the water fresh. Thus, Aquaponics systems are integrated systems combining aquaculture and horticulture into a common eco-culture. It is based on reusing water and nutrients from aquaculture into a production system for plants, utilising the nutrients in the effluent water for production of vegetables.

In aquaponics, the fish waste water is distributed to the plant root base (replacing the traditional hydroponic nutrient mix) providing a food source for the growing plants. The plants provide a natural filter, and the water can be reused by the fish. This creates a mini eco-system where both plants and fish can thrive. The ideology is far from being new, and the methodology is currently used naturally in Asia and has been tested and implemented in a number of countries such as in USA, Australia, Central America and Canada.

With growing populations in the world, increasing demand for food and decreasing farm land, aquaponics can be one of the solutions for feeding people around the world. Aquaponics is however still in its infancy commercially, but as this technology develops, hydroponic growers can introduce fish to their operations and aquaculturists can introduce plants to their production. The interest for aquaponics is rapidly increasing in Europe and this approach is believed to have an interesting potential to be one of the future production methods for local food, e.g. in urban production with small units designed for homes and restaurants. Some of the important advantages of aquaponics include:

Aquaponics can be carried out virtually in any climate and anywhere

Aquaponics can increase the productivity of any given space

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Fish provide the fertilizer for the plants, eliminating/decreasing the need for chemical fertilizers in plant culturing

The plants help to purify the water, eliminating/decreasing nutrients in the effluents from fish production in aquaculture

An efficient recirculating system conserves water and thus energy for heating and cooling

Three main aquaponics production methods are currently practised; the nutrient film technique (Figure 1), floating rafts (Figure 2) and grow beds (Figure 3).

Figure 1. Nutrient film techniques. In nutrient film technique systems a thin layer of water is flowing in plastic pipes, commonly 10-15 cm in diameter. The plants are grown in pots that are placed in holes made in the plastic pipes so they can reach the nutrient rich water below. The system is very simple and therefore relatively cheap and easy to handle. The system is suitable for salad, herbs and other small plants.

Figure 2. Floating rafts. The floating raft system is based on large tanks. The plants are grown in pots that are placed in holes on plastic plates (often polystyrene foam) floating on the water. The system is excellent for salad and other vegetables.

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Figure 3. Grow-beds. In grow-beds systems, gravel or sand is used to stabilize the plants. It also works as an aeration system and provides better stability for higher plants. In practice all plants can be grown in such systems.

In aquaponics systems, the effluents from one system therefore become a valuable raw material for another system. The effluent water from aquaculture is rich in nutrients required for plant growth and the plants clean the water through utilization of the nutrients and the water can then be recirculated to the fish. The re-use of effluent water from aquaculture production therefore changes waste water into a by-product that can be used for plant production as the plants take up the nutrients from the water. This minimises the negative environmental impact of the effluent water from aquaculture and moreover the plants bind carbon dioxide from the atmosphere. Such systems therefore represent a natural circle which minimizes the environmental impact of aquaculture production. Hence, if successful and economically beneficent, aquaponics systems could become a breakthrough for land-based aquaculture stations whereas the environmental impact of the effluent water represents one for the bottlenecks for the production capacity of land-based units. Moreover, this provides opportunities for increased local food production which will result in reduced transport of food products and food ingredients, thereby contributing to increased food security and overall sustainability of food production.

The reuse of water from the aquaponics in the aquaculture production system will furthermore minimize the requirements for water addition into the system. A 100% recirculation would mean no water-outlet and water replacement would then be limited to the replacement required due to evaporation and absorption by the plants. Thus, aquaponics integrated into an aquaculture plant results in a natural circulation of water resources and organic material, providing a sustainable production system with minimal or even no carbon footprint. Such integrated systems providing optimal use of water resources, energy and organic material and minimising waste could become the breakthrough for European aquaculture. Combining aquaponics into an aquaculture farm may therefore be viewed as a step towards a more sustainable and economic competitive aquaculture. Implementation of aquaponics within the Nordic countries will therefore have the potential to open for innovative opportunities for agriculture and aquaculture and thereby provide new jobs and contribute to local production and improved resource management. This will contribute to economic growth and rural development and enhance food security.

For water recirculation between 50-70% aeration is needed with oxygenation at the same time CO2 is removed. Using water recirculation below 50% only oxygenation is required. For water recirculation above 70%, a bio-filter is needed in aquaponics systems. A bio-filter contains microorganisms that change ammonium from the fish to nitrite and then to nitrate (Figure 4). Ammonium and nitrite in only low concentrations are poisonous for the fish and the plants need nitrogen mainly in the nitrate form. Hence, without an effective bio-filter the system would not work. Approximately 2-4 weeks are required for the establishment of the appropriate bacterial community required for the bio-filter to function well in the system.

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Figure 4. The interplay of water use and water recirculation in aquaculture Recirculating Aquaculture Systems (RAS).

4. Implementation of aquaponics in the Nordic countries The objective of the project was to build on existing knowledge on technical and economic feasibility of aquaponics systems for implementation of aquaponics into Norwegian and Icelandic aquaculture. The partners from each country are companies in the aquaculture and horticulture industry that are interested in implementing aquaponics into their operation system. Collaboration was established between Iceland and Norway in the beginning and with participants from Denmark joining the group at early phases. Relevant specialists from R&D institutes have been involved in all the Nordic countries and a number of graduate students were involved in the project work at different levels.

The project has provided excellent synergy in joining the appropriate actors work within the Nordic countries, carried out in close collaboration with Canadian actors in Ontario, and various other collaborators such as Tropenhaus in Switzerland, thereby building further on the experience and knowledge already gained. The Canadian network has provided valuable knowledge of the principles and practical application of the water systems that have been developed (Crop Diversification Centre South (SRCS), Brooks, Canada). This includes the pros and cons of different fish species, vegetables, culinary herbs and ornamental flowers for such integrated production system. Knowledge on technology development, water management and quality as well as system operation has furthermore been gained from Canadian and other collaborators worldwide. This knowledge coupled to the experience of the Nordic participants from aquaculture and horticulture has helped the construction of pilot plants for Nordic climate, with optimal choices of fish and plants, with the overall aim to promote the unique position possible for Nordic aquaponics integration systems. The project may furthermore be viewed as the first steps towards the formation of a Nordic aquaponic network which will continue and built further on in a new project that recently got funded by the Nordic Innovation Centre (Aquaponics – NOMA project, planned 2012-2015).

The selection of fish species as well as plant species for an aquaponics production need to be based on climate, ambient light conditions, access to water of the appropriate temperature and quality, energy reserves and various other conditions. The ratio of nutrients from aquaculture production is such that 10 times more plants will be harvested as compared with fish, however, depending on the plant species selected for the system. The choice of the appropriate plant species furthermore involves productivity, production costs and sales revenue among other factors. The high energy requirements (temperature, light etc.) are therefore of high importance when selecting plant species for the aquaponics system and call for highly efficient production, large production volumes and/or the selection of higher-value plant products and aiming for niche markets for the products.

Native fish species of the Nordic area has been selected for the aquaponics pilot plant in both Norway (brown trout) and Iceland (Arctic charr). The access to warm water reserves of high quality furthermore offers the possibility to include a warm-water species in Iceland and

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Tilapia has therefore been selected for the aquaponics pilot plant at Matorka for comparison to the Arctic charr. A small-scale test system has been selected for the Norwegian pilot plant, while in the Icelandic part of the project the focus is on larger production units by utilising the geothermal heat and land space.

4.1 Implementation of aquaponics in Iceland

Food imports have been an important measure for domestic food supply in Iceland due to largely unfavourable conditions for large-scale horticulture. A trend towards greenhouse production has however increased the availability of locally produced fruit, vegetables and ornamental plants. Icelandic greenhouse producers take advantage of geothermal energy for greenhouse heating and can use locally mined pumice as substrate for hydroponic crop production. Cheap imports from other countries and higher production costs in Iceland are the major obstacle for further expansion.

Warm water aquaculture is important for future production of food due to the rapid growth, low production cost and relatively low risk. It is the main production method behind increase in farmed fish and has been growing very fast in Asia. There is a need for increased warm water aquaculture in Europe, introducing new fish species that can grow fast to market size and it is of also importance to include species low in the food chain for increased sustainability and healthy food. There is a lot of knowledge regarding cheaper and more sustainable feed raw materials, polyculture and integrated systems that need to be further explored and developed into business ideas. This project aims for developing profitable competitive land-based aquaculture using sustainable methods, designing aquaculture stations with integrated techniques focusing on relatively cheap solutions with raceways and optimization of breeding many species in a common system. Integrated aquaculture has not been explored and developed into large commercial units in Europe and this could become the breakthrough needed for European aquaculture.

Polyculture of warm water species provide healthy ecosystems, but need careful development and design of the system, especially water management, i.e. how water is recirculated between different species, for optimal utilization of water, energy and nutrients, without increasing the risk of diseases and dangerous contaminations. Polyculture is providing new opportunities for aquaculture, not least land-based aquaculture with new warm water species. Utilization of geothermal energy for warm water aquaculture provides a whole new perspective for land-based aquaculture in Iceland and other places with geothermal heat resources available. The implementation of novel techniques and new species focusing on the utilization of excess geothermal heat in an economically and environmentally beneficent way would increase the competitiveness of the Icelandic aquaculture industry and result in a lot of spin-offs.

Aquaculture is an increasing economic sector in Iceland and due to favourable conditions it has large potential for expansion. Currently there are 45 registered farms with an aquaculture production of about 5000 tonnes. Total production is expected to double by 2015. Stricter environmental regulations for aquaculture farms enforced over the past years have however led to increased production costs and demands for more sustainable practices in aquaculture have led to innovative approaches in this field of research. The integration of hydroponic plant cultures into recirculating aquaculture systems is therefore considered a promising approach. Hereby, water treatment can be intensified while at the same time having the potential to lower water treatment and waste water discharge costs through production of a secondary high value product. Further research must be conducted in the field of aquaponics to identify its potential for the Icelandic market and identify the special requirements for aquaponics systems in Iceland. This includes experimental trials and economic analyses to determine the feasibility of commercial aquaponic systems.

The plants need about 16 nutrients. These nutrient are classified in macronutrients or compounds that is needed in larger quantity and micronutrients or trace element that the plants needs in less quanity. The main macronutrients that is needed are carbon (C),

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oxygen (O), hydrogen (H), nytrogen (N), kalíum (K), calsium (Ca), magnesíum (Mg), phosphor (P), and sulfur (S). Carbon, oxygen and water is mainly received rom water and carbondoxide but the rest is disolved in the water. Therefore the water composition is important and it fullfills the requirement and the components in the water is in right balance. One compound can block absorption of another one. The pH in the water for the plant needs to be near pH 7.

The objective of the Icelandic part of the project is to develop and build an experimental aquaponics pilot plant, incorporating the advantages of local conditions in Iceland and adapting the system towards the needs of the established Icelandic aquaculture and horticulture sector as well as towards future demands. In the Icelandic part of the project, the focus is on larger production units and the utilization of geothermal heat. The aquaponics pilot plant operation will be designed and tailored to the combined arctic charr and tilapia aquaculture at Matorka’s farm at Fellsmuli in South Iceland. Tilapia is an omnivore species and protein-rich green growth commonly produced in aquaponics may therefore serve as a large part of their feed. Moreover, remnants from the tilapia can be used as part of the feed for the arctic charr. Thus, the system can be designed to balance the different factors providing an optimal economic and eco-friendly model.

Implementation at Matorka’s production site

Different approach for integration of aquaponics in Iceland were considered. One of the solutions suggested involved the construction of a Rovero greenhouse over the concrete raceway (6 x 20.5 m) and integration of the aquaponics into the aquaculture production at Matorka’s facilities at Fellsmuli, aiming on large quantities of plants produced. A mixture of waste-water from the production of tilapia (28°C) and arctic charr (8°C) would then be used for the production of tilapia in the raceway (~23°C) and the waste-water used for plant production.

The design included an isolated part in one end of the raceway, a buffer-tank with controlled conditions with respect to nutrients and temperature (Figure 5). The nitrate and phosphate concentration in the buffer-tank would need to exceed the concentration of nitrate in the other part of the raceway where the fish is kept. The appropriate conditions will be achieved either through control of the number of fish and feed influx in the buffer-tank (i.e. the maintaining the appropriate ratio of nutrients) or by adding waste-water from other production units in order to adjust the nutrient content. In order to obtain such conditions, a drum-filter would be required in combination with the bio-filter and worms in a clay substrate might be used for decomposing of fish faeces. The pump would be placed in the buffer-tank and hydroponics pipe systems placed at the sunny side of the greenhouse and the clay-bed at the other side. Lamps and lighting system would furthermore be required for the greenhouse.

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Figure 5. The greenhouse idea. The idea involved the construction of a greenhouse over raceways used for fish production at Matorka’s facilities.

In this system, water is pumped from the buffer-tank, through the bio-filter and to the clay-bed, using a high-low tide system. This will give continuous inflow to the beds and tide effects with 40 minutes intervals. From the beds, the water runs to the hydroponic pipe system and from there to the fish tank. A high-low tide system would involve plants that require higher concentration of nutrients (parsley, coriander) and the hydroponics would contain plants with lower requirements for nutrients (salads).

The pipes would need to be carefully selected, whereas some types of effluent pipes leak chemicals that may affect the growth of the plant as well as the fish. Food-grade would therefore be necessary (PVC, PE, PP etc.). Other things to consider include the selection of plants with "similar" requirements for the two production compartments, the clay-bed and the hydrophonic compartment. The requirements to consider include pH, ammonia tolerance, light/unit production and the concentration of oxygen as well as nitrate, phosphorous and sulphur in the effluent water. Salads and spices could be of interest, whereas relatively high nutrient concentrations are required for the growth of cucumber and tomato.

Between 60-100g of feed is needed for each m2 of plant production on a daily basis (www.aquaponics.com). The energy requirements are estimated to be around 250 kWh/m2, with 75-80% estimated to be covered by lamps. Production costs for such system are estimated to be around 60 000 ISK/m2, including water system, lights etc.

Another approach considered involved the construction of a pilot plant unit, allowing better control of all parameters but the production of only small quantities of plants. Such system would, however, allow the testing of various types of plants for the production and in triplicate/quadruple. A plan for such a pilot plant at the experimental facilities of Matis (Keldnaholt, Reykjavik) was carried out by a German MSc student, in collaboration with Matorka’s and Matis experts in various fields.

The design consists of a 200x200cm fish tank for an approximate water volume of 2m3 and eight 210x60cm troughs simulating the hydroponic element. The recirculating aquaculture system (RAS) at the Matís test site already consists of the basic RAS set-up and equipment, including fish tanks, piping, heat exchanger, thermostat, drum filter, bio-filter, aeration, storage tank and automated feeding systems. Only minimal expenditures would be required for the construction, with total costs estimated to be only IKR 261.565 in addition to water and electricity costs. The hydroponic element would be built next to the fish tanks to utilize free space and minimize piping. The hydroponic elements will be filled with inert substrate for hydroponic plant growth. Water from the storage tank trickles onto the substrate from PVC

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pipes located above the surface for even distribution and additional aeration. The outlet water runs directly back into the pump pit where it is recirculated through the system components and is pumped back to the storage tank. Simple gauze filters located at the outlet of the hydroponic element can collect excess substrate material before accumulating in the RAS. Valves can regulate the water flow-through for the hydroponic elements and can induce a backwash mechanism. The bio-filter is operated in a by-pass and can be cut off for plant-substrate bio-filtration experiments. Prior to the experimental trials, the plant-substrate will be inoculated with bacteria from the RAS bio-filter and fed with a nutrient solution. Six 400W metal halide lamps will be places over the hydroponic set-up to assure optimal growth light distribution. The pilot plant can be easily dismounted and re-designed for future experimental research.

Figure 6. An example of a design for an aquaponics unit. The experimental set-up of the hydroponic element consists of six troughs with two different substrates (3x pumice and 3x clay) and two control groups (one with soil and no water supply by the RAS and one with no substrate working by the Nutrient Film Technology (NFT)). Each trough contains two types of fast growing crops arranged on a random basis. The fish will be fed according to the estimated bio-filter capacity of the substrate.

The pilot plant construction would allow for testing of two different crops in three different substrates (pumice, clay, soil) and with two different controls (one with soil and no water supply by the RAS, and one with no substrate working by the Nutrient Film Technology), each in triplicate troughs. This would allow the determination of the following:

o Plant / fish growth under given circumstances o Nutrient uptake by plants (de-nitrification) o Bio-filter capacity of the plant-substrate (trickling filter with pumice and clay) o Problems, difficulties and improvements for the suggested plant-substrate bio-filter o Backwash or suitable solid removal system for plant-substrate o Comparison to soil-only and NFT control group o Water quality and nutrient content during the experimental trial

There exist many opportunities in the utilization of geothermal water and waste water from geothermal power plants to establish a whole new industry in warm water aquaculture, producing new competitive species for mass production and export. The species of interest commonly live at optimum temperatures of 20-30°C and can be cultured in polyculture systems which can further be integrated into sustainable healthy ecosystems including aquaponics or algae production.

The implementation of sustainable warm water aquaculture in Iceland will introduce a whole new green food industry, utilizing local resources, building an ecological food park based on integrated systems with polyculture, aquaponics, tailored feed from local raw materials and added value food production with focus on healthy and safe food for export (Figure 7). Natural green production circles optimize the utilization of energy, water, organic waste material, land and other local resources. This will provide conditions favourable for the sustainable growth of Icelandic food production with focus on utilization of geothermal heat,

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ensuring both adequate supplies of seafood and vegetables and protection of the environment.

Figure 7. A diagram showing the aquaponics production concept at Matorka’s facilities in Iceland.

Figure 8. Tropenhaus in Switzerland,showing aquaponics with plants and tilapia.

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In this project the focus has been on new warm-water species for aquaculture, initiating commercial production of Nordic tilapia in relation to Arctic charr production, designing a system for utilising the effluent water from the fish rich in nutrients for hydroponic production of salad and herbs. The work done so far has been successful and both the Arctic charr and the Nordic tilapia have been well received on the market. The Arctic charr aquaculture is a promising business but needs to be developed further especially regarding the water management and utilization of other natural resources. New species like the warm water species tilapia are growing to a market size within 7-9 months compared to 1,5-2 years for Arctic charr. Moreover, the warm water species can utilize residues feed and oxygen in the effluent water from the Arctic charr. The effluent water rich in nutrients from the warm water species could then be used for green house production. This creates exceptional opportunities for poly-culture in Icelandic aquaculture businesses. Furthermore, the local production methods developed could be implemented in European aquaculture industry with other species, especially in places where there is abundant geothermal heat and/or waste heat from power plants or other industry.

Matorka has access to geothermal water and indoor facilities for warm water species, juvenile production and green houses, and access to self-running cold water for the on-growing of Arctic charr. Matorka´s farms were smolt farms producing wild salmon and trout juveniles for the rivers and lakes in the vicinity of the production sites. The facilities have now been changed to accommodate the production of Arctic charr and Nordic tilapia for the food market. At Matorka´s site, 4-5 different plants, salad and herbs will be tested, and possibly also duck weed and/or other fresh water plants rich in proteins and which could then be utilised directly as feed material for the tilapia. The original plan was to build a pilot unit that does not need new permission additionally with what Matorka has today in Fellsmuli. The design of the aquaponics pilot unit is finished and the facilities and the pipe system have been prepared for the new aquaponics pilot unit (Figures 9 and 10).

Figure 9. Raceways under construction at Matorka’s site in Fellsmuli, South Iceland (January 2012).

The design of the raceway (designed by ArkÞing) is transferred from Denmark, but adjusted to Icelandic conditions. The raceway was designed with respect to the conditions at Galtalækur and with a smaller version for Fellsmuli. The pipe system is designed in such a way that the raceway can be used for production of cold water or warm water fish species, also by dividing the raceway into two distinct parts with warmer water in one part and colder water in the other part.

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Figure 10. An overview of the pipe system at tha aquaculture facilities of Matorka in Fellsmuli.

The new pipe system is designed in such a way that the temperature can be adjusted in the aerators and hence, colder water used for the charr tanks and warmer water to the tilapia tanks. The design of water recirculation systems at Matorka’s facilities included design of the pipe system, LHO aerators and flow for maximum recirculation of the inlet water. The water recirculation system allows up to 70% utilization of the culture water, meaning that instead of requiring 45.000 litersl/day, thousand times less water is required for the production of each kg fish.

The production volume at Matorka is increasing steadily. The tank volume for Nordic tilapia production has been increased tenfold and the recirculation of water is becoming approximately 70%, yet without using biofilters. This has been done by a new water system were the water is recirculated first in the Artcic charr tanks and then transferred through a system were the water is aerated and ajusted for the Nordic tilapia and then recirculated through the Nordic tilapia tanks. The final part of the system is composed of raceway and filtration system for the water prior to releasing as effluent to the river.

With increased recirculation in aquaponics systems the production of Nordic tilapia could be increased substantially, and this would also include an enormous production of vegetables and/or fruit in green houses. Aquaponics systems are today mainly known as small production units for urban farming, but the plan is to test if large units utilizing geothermal water could become one of the future green growth production methods of food.

The NFT system has been selected as the best system for aquaponic system especially because it is rather light and mobile and can easily be modified as well as it is rather inexpensive.

4.2 Implementation of an aquaponics in Norway

Implementation of year round intensive production in protected environment, such as greenhouses, implies high production costs in temperate climates due to energy cost for light and heating. Depending on the green house, energy cost per year can vary between 30-50% of total production cost (typically between 300-750 kWh/m2). It will therefore be essential for the profitability of the farming techniques to optimise the production with respect to

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greenhouse technology and the choice of plants and fish, in order to reduce the energy cost in the production. This will reduce the number of species of plants and fish that can be used. Also, investment to reduce energy cost will be higher in temperate zones than in warmer climates. This will not be different from ordinary production in green houses in the same climates. However, it will be possible to share the energy costs on two productions, both the intensive fish production and the intensive plant production. Investment in new technology to reduce energy cost is essential.

Norwegian production of fish and products value is shown in Figure 13. The Norwegian consumption from agriculture is 50% self-supported by indigenous production. The Norwegian production of fish is 20 times the consumption, and Norway is the second greatest exporter of seafood in the world, including products from fisheries and aquaculture.

Figure11. Produced volume for the most important cultured fish species in Norway1997-2011; Atlantic salmon (top left), Rainbow trout (top right) and other fish species (bottom).

The development in primary production in Norway is similar to the development in the rest of the society, with new knowledge and technology being developed in order to reduce labour costs stimulate an increased production, higher yield, new products and reduced unit cost. However, this development contributes to decreasing number of producers, and the recruitment to these productions is a challenge. Number of companies with production in greenhouses (>300 m2) has been reduced from 851 (1998) to 454 (2010). The production of vegetables in greenhouses has in this period increased, and was in 2010 30.000 tonnes. Total Norwegian production of vegetables in 2010 was 146.121 metric tonnes (MT).

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However, only a small amount of the production in Norway, both in aquaculture and in greenhouses, is produced with intensive technology as hydroponics or recirculated aquaculture systems (RAS). Moreover, the Norwegian aquaculture industry is mainly producing in sea water using rather large sea cages. One exception from this is the production of juveniles of salmon and rainbow trout (smolts). This production is carried out in fresh water, and an increasing number of the facilities are now looking into the possibilities for intensive production such as RAS due to lack of water resources and available suitable locations. In addition, the industry is getting more restrictions in terms of effluent loading, and new methods for collecting, keeping, conserving and utilising effluent water are currently being developed and implemented. Norway therefore has good opportunities to contribute in the development for an integrated production of plants and fish based on optimised energy consumption. Especially the development of integrated production systems based on agriculture, bio energy and land based aquaculture have a good potential.

The required water exchange in land based aquaculture is decided by the following limiting factors: Oxygen (O2), Carbon dioxide (CO2) and Ammonia/Ammonium (NH3/NH4). With the introduction of recirculation of water, particles and metabolites must be removed and O2, temperature and pH controlled. In facilities with very low requirement for water exchange, biological filters are introduced for aerobic nitrification by the oxidation of NH3 to NO3 (nitrate) To further reduce requirement for water, anaerobic de-nitrification can be introduced, by reducing NO3 (nitrate) to N2 (nitrogen gas). In aquaponics the plants replace the filters for de-nitrification by using the nitrate (and other minerals) for growth. With the addition of wet composting of the particles (mineralisation of faeces and uneaten feed), there is a potential to reduce effluents from aquaponics to almost zero. Without the use of de-nitrification or plants, the effluents from the recirculated fish facility will be the same as in a flow through system, only more concentrated due to lower water exchange. Some mass-balance calculations for N and P in aquaculture production are shown in Figure 12.

Figure 12. Mass balance for nitrogen (N) and phosphate (P) in feeding of fish when all feed is eaten. Thus, uneaten feed will add to this (modified after Bergheim & Braaten, 2007).

Inland aquaculture in Norway is mainly limited by public regulations regarding the risk for:

Escapes of fish

Spreading of diseases to wild fish stocks and downstream aquaculture facilities

Pollution by organic matter and nutrients

The main consequences of these regulations are that only relatively advanced, efficient and expensive land-based facilities are allowed. This is mainly due to strict regulations allowing only small amounts of organic load into surrounding environment. Subsequently, investments

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become very high and elevate the threshold for the industry’s economical sustainability. Also, due to the risk of escapes, usually only local stocks are allowed for inland aquaculture, which make the use of breeding programs for the fish difficult. The use of recirculation in combination with plants and with almost no effluents could help solving these problems. In addition, sea water cultivation of Atlantic salmon and rainbow trout is the only commercially established production today. Other species that could be of importance as niche products for intensive production in aquaculture are Arctic charr (Salvelinus alpinus), brown trout (Salmo trutta), perch (Perca fluviatilis) and powan (Coregonus lavaretus). However, neither the production nor the market for these species has been developed. Profitability is a major concern when considering the use of recirculating systems. Also, profitability of aquaponic systems will be dependent on local markets and costs specific to the area for the production. It is therefore important to establish budgets to gain experience with production given local conditions.

Implementation of an aquaponics pilot plant and a research facility in Norway

For developing aquaponics in Norway, the main areas to work with have been identified and involving the following activities:

Establish pilot plants to gain experience with local production

Establish a R&D facility to help to develop the industry

Identify best suited plant species for the production

Included market research for local production

Identify best suited fish species for the production

Included market research for local production

Implement energy efficient solutions for greenhouses for year round production

A new aquaponic company, Aquaponics AS, has been established with a pilot production at Bjorå Gartneri, Evje (Figure 13). Aquaponics AS received public grants from the Government of Norway through the regional research council (department of Norwegian Research Council) to establish and develop a new concept for Aquaponic production in boreal areas (cold-water species). The woek is carried out in co-operation with Niva, Bioforsk, Feedback Aquaculture and Aqvisor.

There are two glass greenhouses on the property and the main production is tomatoes and cucumbers. In the main production the greenhouses is closed down during the winter. The facility wants to upgrade their production, and has decided to investigate the possibilities within aquaponics by redesigning one of the greenhouses of 200 m2 for a year-round production. Total production area in hydroponic tanks will be approximately 65 m2. The fish in the facility is placed in a nearby building and the water is pumped to the greenhouse from the fish tanks.

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Figure 13. Overview of Bjorå Gartneri with the two glass greenhouses.

The facility is installed with a fully recirculated aquaculture system (RAS) and is licensed for a yearly production of 6 tonnes of brown trout (Salmo trutta). The system is based on a hydroponic deep water system (DWS) for production of plants to clear the water for metabolites and other nutrients from the fish production. The use of DWS and raft production is recommended for commercial production in aquaponics, whereas the extra water volume in the plant production contributes to better stability in water parameters which is good for both the fish and the plant production. The water quality in the fish tanks has to be maintained according to public regulations and FOR 2008-06-17 nr 822 where it says: “Fish must at any time have access to sufficient amounts of water of such a quality that the fishes achieve good living conditions according to species, age, developmental stage, weight and physiological and behavioural needs, and not be put in danger to be challenged with unnecessary stress or harm, also included damages as deformities. Water quality and interactions between different water parameters shall be monitored after need. With any danger of harm or unnecessary stress to the fish, shall effective and preventive measures be implemented. The amount of metabolites accumulated in the water shall be within safe limits” (see Table 1).

Table 1. Guidelines for water quality parameters in fresh water aquaculture (FOR 2008-06-17 nr 822).

Parameter Value

pH in water 6,2-6,8

O2 saturation 80-120%

O2 in water > 90%

O2 out water > 80%

CO2 < 15 mg/l

Total organic material < 10 mg/l

Al < 5 g/l

NO2 < 0,1 mg/l

TAN < 2 mg/l

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At Aquaponics AS at Bjora Gartneri, the plants will be grown on rafts in the DWS hydroponic tanks (Figures 14-21) and the estimated production volumes have been calculated based on licenced volumes for the site (Table 2).

Figure 14. Schematic water flow in the facilities of Aquaponics AS.

Aquaponics ASwater flow/water treatment

Q evapo = evaporation from plants

Q in total = intake water

Q in fish = water to fishtanks

Q out fish = water out from fish tanks

Q in plants = water to greenhouse

Q out plants = water out from greenhouse

Q bypass = adjustable water bypass ing greenhouse

Q return = return of cleaning water from drumfilter

Greenhouse

Fish tank

Q in total

Q out plantsQ in fish

Q evapo

Drum filterBio filter

Q out fish

Particle collection

Aeration

Q bypass

Q return

Q in

plants

Skimmer

pH

Sump

Temp.

O2

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Figure 15: Overview of the RAS in the aquaponics system of Aquaponics AS. The water flows from the biofilter to the plants and returns to the skimmer and aerator. Courtesy by Hobas.

Figure 16: Photos of drum filter, particle collector (flush water from drum filter), bio filter, aerator and skimmer at Aquaponics AS.

Particle collection

Bio filter Aerator Skimmer

Drum filter

Fish tanks

Skimmer

Aerator

Bio filter

Drum filter

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Figure 17. Photos of oxygen generator, air compressor and fish tanks at Aquaponics AS.

Figure 18. Syrtveit fish hatchery. Brown trout ready to deliver to Aquaponics AS.

Figure 19. Photos of hydroponic tanks for plant production in the greenhouse at Aquaponics AS.

Hydroponic tanks

Return sump

Hydroponic tanks

Oxygen

Air compressor

Fish tanks

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Figure 20. Hydroponic tanks with test production of plants using hydroponic fertilisers at Aquaponics AS.

Table 2. Parameters in the production of fish based on volume licensed for Aquaponics AS.

1)

42% protein in feed

Figure 21. Total standing biomass of fish in the facility based on licensed volume. One tank is harvested and refilled once per month.

Parameter Unit Amount

WW fish in Kg per fish 0,1

WW fish slaughter Kg per fish 0,6

Production time Months 6

Daily specific growth rate (SGR) % 1

Feed conversion rate (FCR) Kg feed per kg growth 1

Number of tanks # 6

Total biomass produced Kg per year 5242

Total feed used Kg per year 5242

Average daily feed used Kg per day 14,4

Total production TAN 1)

Kg per year 158

Hydroponic tanks with plants

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Rakocy (2010) has calculated a ratio of between 57-100g of feed per m2 of plant production area. The ratio depends on many factors such as plant species, protein in feed, feed factor, particle collection and more. Factors as low as 20g feed per m2 has been reported. With the high protein feed to trout, it is reasonable to use a factor of 50g per m2, which means that 1 kg of feed used can support 20m2 of plant production area. In our case and with full production, this will mean a plant production area of 20 x 14,4kg = 288m2. The facility only have 65m2, so based on 50g per m2 only 3,25kg of feed can be used per day (65/20). Based on 1% SGR and a FCR of 1.0, this corresponds to an average standing biomass of 325kg, which is only 25% of the full capacity of the fish tanks.

Aquaponics AS will use the current research project to develop and document new aquaponic technology suitable for Norwegian environments, combining fish and plant production in a sustainable way. The work has been organised in four work packages:

Document growth and quality of brown trout.

Finding the right plants for the production – document growth and quality of the plants.

Optimise technology and routines for good synergy between plant and fish production.

Establish good methods and routines for handling discharge to prevent pollution and spreading of disease to surrounding environment.

The recirculated aquaponic system has been constructed as a zero discharge system and it must be proven that this is possible. The production started august 2012, and the first fish have arrived.

Research facilities.

Bioforsk Øst, dpt. Landvik in Grimstad will establish a R&D facility for aquaponics. In this facility it will be possible to do experiments with both plants and fish species. The R&D activity will be performed in close co-operation with the industry, and will strive to develop aquaponic production suited for temperate climate for making it profitable and sustainable industry. Bioforsk is a research institute with competence on high international level within agriculture, food production, plant health, environment and resource management. Bioforsk is organised under the Department of Food and Agriculture and has seven research centres with 450 employees. Bioforsk Øst has the national responsibility for the research on vegetable production, and also they have a regional responsibility for research on bio energy.

The research facility will be ready engineered in 2012, and will be established in spring 2013 (Figure 22). The technology to be installed in the facility will be bought ready made from the producer, based on the system developed on University of Virgin Islands (UVI-system) (Figure 23). This system has also been further developed by the Crop Diversification Centre South in Alberta, Canada, which have adjusted the system to greenhouse production in a temperate climate. The system is based on plant production on rafts in a deep water system. A close collaboration between Bioforsk and CDCS (by Nick Savidov) has been established for this purpose.

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Figure 22. Overview picture of the research station of Bioforsk Øst, Landvik, Grimstad.

Figure 23: System layout of the UVI system developed by Rakocy on University of Virgin Islands. The system is being built in different sizes, but with the same ratios as shown in the layout.

One of the reasons it has been decided to install technology from an established producer, is the cost of establishing a RAS based on the currently available technology. To illustrate this

Fish rearing tanks = 30% of total water volume

Water treatment tanks = 10% of total water volume

Hydroponic tanks = 60% of total water volume

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we have put a budget for a land based farm producing 100 tonnes of fish per year (Table 3). Breakeven price per kg (round weight, not gutted) in this example is about 58 NOK per kg, financial costs not included. This is only possible in niche markets. To have a sustainable production, the budget will have to be much more robust, and the production cost per kg must either be reduced or selling price must be increased. The costs that can be reduced with fish production in combination with plant production (aquaponics) would be personnel costs, other operating costs as energy costs, and financial costs (Table 3).

Table 3: Breakeven operating profit budget for a land based RAS for an annual production of 100 tonnes. Budget based on known Norwegian industrial costs (currency in NOK).

To balance a production of 100 tonnes of fish (with a FCR of 1.0 and a standing biomass of 25 tonnes), a plant production area of 5000 m2 would be needed. It will be difficult to produce 100 tonnes of fish and have a plant production area of 5000 m2 in local as well as niche markets in Norway. In order to make this industry sustainable, it is necessary to have small to medium farms that produce both fish and plant fresh to local/regional markets. This means that the technology can be more “low tech” and hence, more affordable for the farms.

Based on available indigenous species, it will be necessary to carr out experiments with Arctic charr (Salvelinus alpinus), brown trout (Salmo trutta), perch (Perca fluviatilis) and powan (Coregonus lavaretus) for evaluation of suitability of these species in aquaponic production in Norway. For a good economy in the production it will probably be necessary to produce niche products of both fish and plants. Inland aquaculture in fresh water is limited in Norway. The production per year is approximately 650 tonnes, produced on 20 farms (Tables 4 and 5). Cultivation of fish to consumers in fresh water in Norway is done in land based systems, and mainly in flow through systems. It is mainly produced fish of 500-1000 grams, and only arctic char, rainbow trout and brown trout is produced. The producers usually control the whole value chain from egg to market. Indigenous fish is caught, stripped for eggs, hatched, fed, slaughtered and processed by the farmers themselves.

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Table 4. Commercial fish farms in Norway for inland cultivation in fresh water producing more than 10 tonnes per year (numbers for 2010, U=unknown) (Sintef 2010).

For Arctic charr there was in 2010 nine active licences in fresh water and 2 in sea water (Sintef, 2010). Arctic char is mainly sold as fresh product. The price has varied between 38-46 NOK per kg. Production of arctic char has varied between 300-500 tonnes per year. In 2009 was 63% of this produced in sea water. It will be possible to buy juveniles of arctic char from hatcheries, but it can be a problem with year round delivery.

There is one producer of brown trout for domestic consumption only. The production is 75 tonnes per year. Brown trout is sold as fresh to wholesales. The price is around 80 NOK per kg. There are some hatcheries producing fry to enhance local populations. It is therefore possible to buy fry of brown trout from hatcheries.

In Norway there is no farming of perch. or powan, and not possible to get fry of these species hatcheries.

It could be possible to produce rainbow trout as processed niche product or fresh product. The advantage of using rainbow trout is that it is commercially established, and that it is possible to buy fry all year round. However, due to regulations and danger of escape and spreading of diseases, it is difficult to get new licences for rainbow trout. Establishing zero discharge aquaponic farms could help get new licenses also for rainbow trout.

Table 5. Status and biological bottlenecks for arctic char, brown trout, perch, powan and rainbow trout in Norway (Sintef, 2010).

Arctic char Brown trout Perch Powan Rainb. trout

Commercial yes yes no no yes

Available quality fish for prod.

yes/no no no no yes

Control of life cycle yes yes no no yes

Commercial feed yes yes no yes yes

Knowledge of diseases medium low low medium high

Knowledge prod. parameters medium low low medium high

Knowledge biology Norway high medium low medium high

Potential Norway high medium low medium ***

R&D needs biology medium medium high medium low

Farm Technology Tonnes per year Specie Arctic char Flow through 30 Arctic char Hande Fiskeoppdrett Flow through 15 Rainbow trout Hardanger Fjellfisk Flow through 90 Brown trout Heimtun Fisk Flow through U Arctic char Hongset Røye Flow through 15 Arctic char Haadem Fisk Flow through 35 Rainbow trout Kirkenes Char Flow through 100 Arctic char Lofoss Fisk Flow through 15 Rainbow trout Noraker Gård Flow through 30 Rainbow trout Nymoen røyeoppdr. Flow through U Arctic char Røn Gård Flow through 15 Rainbow trout Sæterstad gård Flow through 15 Arctic char Totak Røye Flow through U Arctic char Trøsvik Fisk Flow through 15 Rainbow trout Tydalsfisk Recirculation 100 Arctic char Villmarksfisk Recirculation 50 Arctic char

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Potential rating (1=high, 3=low) 1 2 3 2 *** ***Not evaluated because new licences are not likely

Aquaponics is a sustainable way to grow vegetables and other plants, where effluents from aquaculture are used for plant production in hydroponics. To have the system in balance – which is necessary for optimal production, the most secure way is to build floating rafts with a lot of water (Figure 24). In this system, environmental factors can be controlled, including air and water temperature, water quality, ventilation, amount of light, insect intrusion, disease and pollution. The concentration of nutrients and which nutrients are available for plant growth is however difficult to control in such systems.

Figure 24. Floating system at Nelson & Pade facility. Photo: Siv Lene Gangenes Skar, Workshop

2012.

Lettuce (Lactuca sativa) is well suited to grow in aquaponics systems, because of high growth rate of a popular healthy food by consumers. High prizes are paid for good quality products and single packed heads. Good varieties are green oak, green cos and butterhead. And if there is some product innovation – like making a bouquet of three varieties of lettuce – the producer could make more money out of each item. To run the system all year around will be expensive for the producer considered energy use for heating or chilling the water, and the use of artificial grow light in autumn and winter. However approx. 60 % of the income will be from the plant-side in an aquaponic system. Each grower therefore needs to investigate the market available for his production site, and carry out marketing research before choosing which crops the farm should produce.

Gravel beds are often used in different aquaponic systems for use in backyard systems (Figure 25). Beds are well suited for maintaining the bacteria for biofiltration, nitrification and efficient plant growth. The wastewater from the fish will ebb and flow in these beds, and they have a high ability to mineralise, dissolve and treat solids from fish water. However, if the fish to plant ratio are too high, gravel beds can clog and lead to toxic (anaerobic) conditions which can kill both fish and plants. Therefore, gravel bed systems do need to be sized correctly to reduce the possibility for this to occur. Another way to grow plants is nutrient film technique, also called NFT (Figure 26).

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Figure 25. Gravel growing beds with different crops. Photo: Siv Lene Gangenes Skar, 2012.

Figure 26. The picture shows NFT growing beds with lettuce. Photo: Siv Lene Gangenes Skar, 2012.

Plants in an aquaponic system need to have good conditions for good healthy growth. They require optimum oxygen, pH, temperature and all the nutrients needed to grow healthy and stay strong for pests and diseases. Several crops have been produced in an aquaponic system and lots of them have grown very well. The soilless plant production starts by seed, cuttings or by transplants. It is important to have good control over pests and diseases throughout the entire production. If the crop starts to look unhealthy, the nutrient balance or imbalance must be checked. Imbalance can be caused by out-of-range pH. The pH should maintained between 6,8 and 7,0 for optimal nutrient uptake by the plants (Figure 27).

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Figure 27. Plant uptake of nutrients dependent on pH.

Another cause of unhealthy plants could be insect pressure. Plants growing in aquaponic systems tend not to get diseases. The disease called “pythium” or “root rot” (fungus) that is estimated to kill 30 % of hydroponically grown plants, is virtually unknown in aquaponics. The conclusion of this can be the fact that while hydroponic system is a largely sterile system, aquaponic systems are full of beneficial bacteria and microbes that help plants to combat disease (Bernstein, 2011). For choosing which crop to grow a proper market research is of help. To make the system profitable, the crops should be fast growing or give high prize in a niche marked. Aquaponics for Nordic conditions require plant varieties that will tolerate low temperatures and limited natural light. Also, since we have four seasons – spring, summer, autumn and winter, each with their characteristic weather conditions – it will be necessary to choose vegetables that consumers are willing to pay premium prices for in each season.

Aquaponics systems are fully recirculated with low footprint and water consumptions, hence these systems can be placed almost anywhere. The market trend is to go for the local produced products, the consumer like to “know” who have produced the vegetables. The consumers also get vegetables fresher and newly harvested because of the low distance from farms to the local/regional market. The products will get known as free for pesticides, herbicides and chemical fertilizers.

In a study for herbs, the annual production in aquaponics varied between species. In trials, water spinach and swiss chard made around 50-60 kg per square meter per year. Amaranth, lettuce, basil, choi, parsley and spinach made around 20-30 kg (Figure 28).

Figure 28. From Nick Savidov and the research in Alberta, Canada (Savidov, 2010).

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Another interesting result seen in aquaponics is the difference in yield between aquaponics and hydroponics. For tomatoes growing in hydroponics the result was 47 kg/m2, and tomato production in aquaponics gave 13 kg more per square meter. Also plant growth in aquaponic nutrient water was higher. Generally, all species that will thrive in hydroponic systems will thrive in an aquaponic system. Many herbs and greens like chards, kale, collards, pac choi and fancy lettuces thrive very well in aquaponics. Also medicine plants, tomatoes and other fruiting crops, edible flowers and micro greens will make it excellent in an aquaponic unit. During the production it is important to observe plant health and the color of leaf. Also the leaf shape can tell if the plant is doing well. Wilting and signs of stress can be useful information for the producer as well as root health. Plants need to have optimum growth rate to be a great partner in clearing waste water from fish – and making aquaponics to a commercial economical winner.

In the past aquaponics excited aquaculturists because the systems recovered waste nutrients and produced valuable by-products. But the hydroponic producers were not interested. Now hydroponic producers are becoming excited because aquaponics represents an organic source of nutrients (some inorganic nutrients are in short supply) and aquaponic vegetables are proving to taste better than hydroponic vegetables.

5. Conclusions and suggestions for future work and Nordic collaboration

The results from the project provide a good overview of possibilities for aquaponics in the Nordic countries, with the overall aim to promote the unique position possible for Nordic aquaponics integration systems. Original project aims have been achieved and foundations for the establishment of aquaponics in the Nordic countries have been built. This work will now continue in a new project, the Aquaponics-NOMA project funded by the Nordic Innovation Centre (2012-2015), where numerous actors are involved within the Nordic countries. Here several experimental trials and economic analysis will be carried out in order to study the feasibility of large-scale aquaponic systems and their potential for the Nordic market. Collaboration with international actors in Canada, USA and Europe has been established and the collaboration further strengthened in the continuing work.

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6. References

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of an Aquaponics System for the Integrated Production of Rainbow Trout and Plants. International

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Aquaponics Network Europe (ANE). 2012. Meeting with other aquaponics growers in Prague.

Bernstein, Sylvia. 2011. Aquaponic gardening: a step-by-step guide to raising vegetables and fish

together. ISBN 978-0-86571-701-5.

Nelson & Pade, 2012. 3-day Aquaponics and Controlled Environment Workshop.

Pantanella, E., Cardarelli, M., Colla, G., Rea, E. and Marcucci, A. 2010. Aquaponics vs.

Hydroponics: Production and Quality of Lettuce Crop. ISHS conference paper.

Rakocy, James. 2011. Aquaponics Q and A. The answers to your questions about aquaponics. ISBN

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Savidov, Nick. 2010. Develop of a 3rd

Generation of Aquaponics System in Alberta, Canada. PP-

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