New specialised diet for recirculation farming

BioMar introduces ORBIT - a revolutionary new feed line targeted specifically at aquaculture in recirculation systems.

Successful farming in recirculation systems is a carefully balanced symbiosis, where the fish farmer both take care of both fish and the bacteria in the bio-filter – and the feed is an important element in this. The new ORBIT feed for recirculation aquaculture meets all the nutritional demands of the fish, but unleashes at the same time potential production capacity by reducing feed impact on bio-filters and by improving water quality. Apart from the gains in fish production, reduced nitrogen content in the recirculation system will also lead to reduced emissions to the surrounding water environment.

- In the development of the ORBIT feed line we had multiple objectives that we had to reach simultaneously, explains Kim Schön Ekmann, Researcher at BioMar’s Research Center in Hirtshals, Denmark. He continues: - First of all we had to secure optimal growth for the fish, but in addition to covering the nutritional needs, we also had to secure that the bio-filter will not be overloaded or obstructed.

In the bio-filter ammonia from the metabolic process of the fish is transformed into relatively harmless nitrate. If the bio-filter cannot cope with the amount of ammonia there will be an accumulation of ammonia in the water which is toxic to the fish. Ammonia is a by-product of the combustion of protein to energy in the metabolic process, and a part of the solution is therefore to reduce the amount of protein in the feed. In order to avoid an impact on feed performance this requires both the use of raw materials with extremely high digestibility and a very precise amino acid optimisation.
- Further, we must secure the absence of small floating particles of faecal origin in the water. The floating particles can be detrimental for both fish and bio-filters since the particles get caught in the gills of the fish and clog up bio-filters, says Kim Schön Ekmann.

The faeces structure of fish fed with ORBIT allows an easy removal of faeces via sludge cones and it has a lower impact on the bio-filters compared to traditional feed types.

Improved economic performance in recirculation farming

Recirculation farming systems typically require larger investments than traditional flow through farms. Maximum utilisation of the capacity therefore becomes a key priority to secure an acceptable return on the investment.

- Trials done in our R&D facilities and in commercial farms together with a number of selected customers during the 2010 growth season showed that we can increase production with up to 25 % in the same recirculation system compared to a standard high performance feed, concludes Kim Schön Ekmann, who expects that the new feed concept, which  in the first place is targeted at trout will soon be adapted to more fish species.

The new ORBIT feed is marketed in the countries around the Baltic Sea, where recirculation already accounts for a significant share of the aquaculture production.

The ORBIT feed line fits perfectly into BioMar’s strategy on sustainable fish farming through and optimal use of resources and reduced emissions to the environment.

Please visit www.biomar.dk for more information.