Clewer Aquaculture is specialised in RAS


Clewer Aquaculture Oy combines the over 30 years’ experience in planning, constructing and project management of aquaculture systems of Kalavesi Consultants Ltd* with strong experience in modern water treatment systems of Clewer Oy.

Kalavesi Consultants Ltd was founded in 1984 to offer consultation and design services to aquaculture. Since then there has been a wide variety of fish farming projects and different design work for fish research stations and commercial farms.

Our skills have been used for designing and constructing both coldwater systems using recycling and warmwater systems utilising excess energy to heat the recycled water. Heat pump and heat exchanger systems are used, if waste energy or heat is not available on site. Cooling of water can be done easily by the same heat pump by only changing some of the water pipe line assembly.

Experience of RAS has been gained at first by building a test system in own hatchery for trout (later arctic char farming). Besides working as a commercial fish farm we have carried out research projects connected to developing the RAS systems. Our latest test experience is with Clarias anguillaris, which is cultured in a warmwater RAS.

Designs for commercial farms and research institutions

We have designed and constructed commercial aquaculture farms in Finland, Sweden, the Baltic countries and Russia for several different species (e.g. rainbow trout, arctic char, pikeperch, sturgeon, eel and salmon). Some of the farms have been new, some have been transferred from flow-through farms into RAS farms.

Technology in farms has included sand filters, moving bed reactors, trickling filters and combinations of these. UV and ozone have been used for disinfection and water quality improvement purposes.

We have also designed and constructed several research and aquarium systems for research laboratories of universities and research centres. We co-operate with several well-known manufactures to provide our projects and sale with high quality equipment for filtration, sterilizing water and pumping water and air. We also use the optimal materials for pipe lines, tank constructions and water treatment to sell safe and reliable RAS and other systems to customers.

Fish handling is done by pumps, screws and grading machines on farms, where they help specially to handle big volumes of fish. For fish feeding we use different equipment produced by the Nordic suppliers.

Wide experience and strong expertise

Our personnel includes experts in different sectors of aquaculture – consulting including planning and project management, practical fish farming experience, teaching in aquaculture studies as well as experience in fish processing (e.g. hot and cold smoked fish).

*Kalavesi Consultants Ltd is owned by Clewer Aquaculture Oy through business acquisition in February 2017.

What is RAS?

RAS is a modern, environmentally friendly and efficient technology for fish farming.

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Customised solutions for commercial fish farms and research institutes across Europe

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