CORDIS - Resultados de investigaciones de la UE

Development of an intelligent fish tank for cost effective aquaculture through control of water quality in each different fish tank.

Final Report Summary - INTELFISHTANK (Development of an intelligent fish tank for cost effective aquaculture through control of water quality in each different fish tank)

The concept behind the INTELFISHTANK project was to develop a cost effective, efficient system for oxygenation and water distribution in an integrated aquaculture tank system for land based fish farming, thereby enabling control of water quality at in each different tank in an aquaculture plant. The principle innovation in this project is the development of a sensor, and control system for oxygenation of water and for control of water speed in order to optimise water quality and growth environment for production of different types of fresh and saltwater fish in land based fish farming industry in Europe. Control of oxygenation of water in aquaculture tanks is essential for developing a fish farming plant with water recirculation. Water recirculation has strong environmental advantages as well as improving the growth environment for biomass by increasing density of fish in aquaculture tanks as well as increasing the growth rate. This improves productivity, reduces costs and improves cost / efficiency and competitiveness of land based fish farming in Europe.

The INTELFISHTANK technology has been tested for free-swimming fish in freshwater in a commercial fish farm. The CO2 concentration in the fish tank has been proven to be very well controlled by the sensor and PLC system controlling the flow rate into the tank. Provided the flow rate and water pressure is adequate, the CO2 concentration stays very close to target level, as decided by the user. This will lead to better water quality, better fish growth and less time spent by the farmer manually changing water flow to the different tanks. The VarioStreamer was proven to supply a very homogeneous oxygen distribution throughout the tank as shown in the position series and the drop in oxygen between inlet and outlet was half that normally recorded at smolt farms in Norway. This improved water quality throughout the tank leads to better fish health and growth and potentially higher stocking densities. The VarioStreamer has provided velocities between 5.6 - 14.1 cm/s. The average velocity, 12.6 cm/s has been proven adequate for self-cleaning of fish pellets and waste products from the tank, as proven by the 24-hour chemical sampling. With the present VarioStreamer and maximum flow rate of 800 l/min, the highest average velocity recorded was 14.1 cm/s. To increase the velocity with the present VarioStreamer with slider design, a greater water flow rate in larger tanks is required. Alternatively the VarioStreamer designed by GUT with a rubber nozzle design has proven to provide higher velocities than the slider design VarioStreamer. However, the hydraulics which control the opening and shutting of the pores are suspected to be less robust during freezing conditions in the winter.

The micro bubble oxygen diffuser failed to produce sufficient micro bubbles to saturate the water with oxygen in freshwater during its initial testing. Its efficiency was estimated at 50 %. It was therefore not used in the subsequent testing. However the future testing of the diffuser in saltwater is expected to show greater efficiency.

The INTELFISHTANK project has resulted in the development of an oxygen gas diffuser, a water streamer and a PLS-system with program for control of the system. A patent has been approved in Norway.

In addition, a patent application has been filed for Chile for the water streamer. The oxygen diffuser will be marketed under the trade name 'SaturOx' which has officially been trade marked and the water streamer will be marketed under the trade name 'VarioStreamer' which has been registered. Oxymat and Artec Aqua are evaluating the possibility of seeking a patent for the control-program.

The INTELFISHTANK technology developed through this project will contribute to improving land-based fish farming. The water quality in each individual fish tank can be user-defined for oxygen and carbon dioxide levels and water velocity leading to an improved and constantly maintained water quality for the fish. This will lead to higher productivity per unit water, better fish welfare and an easier working day for the fish farm employee. These improvements will encourage more sea based fish farms over to land-based farms.

Sea-based farms have many environmental disadvantages such as biomass loss due to algae and jellyfish attack or storms and ice flows. Farmed fish can escape, especially during bad storms and cause genetic pollution to wild populations. Fish disease between farmed and wild fish is more easily spread in sea based operations. Sea based farms occupy attractive coastal situations limiting these sites use for recreation and boating and waste can pollute nearby bathing areas. As sea-based fish farms move to land-based operations, the following EU directives will be fulfilled, the Integrated Coastal Zone Management, many directives concerning environmental improvements to the Common Fisheries Policy and the Water Framework Directive. In addition our technology directly fulfils several of the goals of the strategy for sustainable European aquaculture, many issues raised in the Federation of European Aquaculture Producers code of conduct and welfare issues for fish. More indirectly, improved productivity at land-based fish farms will lead to more high quality seafood available to European consumers and more jobs available to those producing, transporting, processing and selling fish. This should encourage consumers to eat more fish and less meat, leading to 600 fewer cases of food poisoning a year. Manufacturing, selling and servicing the INTELFISHTANKS will bring employment opportunities and improvement of skills in these sectors. The INTELFISHTANK project has not in the past, and does not at present; violate any standards, ethical or regulatory aspects of the exploitation of the project results.