In Europe the future expansion of aquaculture is widely believed to be through land based recycling systems with minimal environmental impact. The global goal of this project was to bring together into one dynamic European network, fish farmers, technology providers, RTD institutes, and companies, with the main focus on water treatment. The network should be able to offer systems tailored to customers' needs all over Europe, in association with equipment manufacturers. Contacts were made between end-users, technical providers and these bodies agreed on the necessity to utilise different pilot production scale farms as a tool to verify recent technical improvements they have made in water treatment. These technical solutions from different fields will be adapted to make an integrated recycling system for the rearing of marine species. Even if Sea Bass (Dicentrarchus labrax) is the farmed species at both end-user sites, the project is species- and region independent.
The overall aim of this project was to improve and validate in full scale the use of innovative technologies for treating sea water, thus validating the concept of a closed circuit system to marine aquaculture. It focused on technical, environmental and economical aspects in land based aquaculture. The project aimed to meet the following targets:
1) Reducing investment costs:
- Use of more cost-effective new technologies
- Precise design and proper sizing for equipment
2) Increasing productivity and controlling inputs in the system
- Minimal use of natural resources (energy, new sea water)
- Maximum fish production per unit food used.
- Optimal fish performances by improved hydrodynamics in rearing tanks
3) Reducing risk factors and developing innovative management methods:
- Strict control of pathogens
- Computerised monitoring
4) Developing a concept fitting with new environmental legislation and reducing wastes:
- Reduction of wastes by minimal sea water exchange and use of natural renewable source of energy.
- Efficient management of effluents and integration of environmental criteria.
The project was genuinely pan European in its approach with trials in the North and the South and provides information of value to fish farming anywhere within the EU. The team overcame technical and organisational problems to achieve improved yields of fish and fish densities. The main questions lie in the area of economics where the high initial capital costs need to be amortised over the annual volume and need to enable the system to be competitive with the alternative sea cage approach.
The report suggests that there may be economies of scale from larger tanks or that the system might be used in conjunction with the existing sea tank approach. The project has wide ranging potential interest within the EU where wild fish stocks are low and where there is a growing demand for farmed fish. The approach provides benefits in terms of jobs in less developed areas, environmental benefits and market benefits in the ability to provide fish of the right size as required. The project team overcame many technical and organisational obstacles in undertaking the project and achieved yields in line with their original objectives. The main concerns lie in the area of the economics of the approach compared with sea cages - particularly given the relatively high initial capital costs.