Floating Fish Farm Unit (3FU). Is it an Appropriate Method for Salmonid Production?

Abstract

Off-shore aquaculture has become an important issue nowadays because of environmental sensitivities and rising conflicts between coastal zone users. From this point of view, a Turkish company has converted a ship into a fish farm in order to gain benefit from the open seas. A 19030 dead weight ton freight ship was transformed into an integrated fish farm to produce salmonids. A 60 m long suction pipe with 1 m diameter, was used for sea water intake from a desirable depth. Sea water was pumped into the fish culture tanks by using 5 pumps each with a capacity of 2500 m3h-1. Pure oxygen generated from an oxygen generator was added to seawater through diffusers for increasing stocking density by means of raised dissolved oxygen of culture media. In this floating fish farm, the initial average weight of Rainbow trout (Oncorhynchus mykiss) was 25±2.7 g. The trout reached 3.7±0.4 kg at the end of 11 months during the production on board. Feed conversion ratio, specific growth rate and stocking density were 1.1±0.1, 1.51±0.3 and 101±2.1 kgm-3, respectively. As a result of the study, trout production on a vessel that enables the use of water from different depth and regulate the water temperature and salinity according to the optimum levels of fish requirements. However, the high costs of crew and energy should be taken into consideration in terms of sustainability of efficient production.

Keywords

• fish culture, ship, rainbow trout, salmon, floating fish farm unit

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