Linn-Catalogue 2019-2020

29 LINN The trouble-free, and stress-free trans­ porting of live fish requires specialist equipment. This includes the fish trans- port tanks themselves, and also the oxygen supply equipment. Selection of the size of transport tank depends on the quantity of fish to be transported, the type of fish, the water temperature, and the duration of the journey. As a guide, it is possible to fill tanks with 75 % water, and 25 % fish, in the case of trout. For a 600l tank, this is equivalent to 150 kg of trout, for a water temperature of 10 °C. For carp species, the capacity can be 50%higher, without problems. Tomaximise the carrying capacity, it is im- portant to use oxygen, diffused through fine-pore diffusers. Where air is used in- stead of oxygen (using 12 V air pumps) the carrying capacity is reduced by 50%. Where oxygen is used, a pressure-redu- cing regulator is necessary, to step-down the pressure from the oxygen cyclinder to approx. 3.5 bar. The oxygen is supplied to the diffusers in the tank by oxygen hose. In addition, an oxygen flow meter should be installed between the oxygen supply and the diffusers. This arrangement will allow the adjust- ment of the oxygen supply according to the amount of fish in the tank. For exam- ple, 100 kg of trout need 2 litres of oxygen per minute, at 10 °C. This doubles, for 200 kg of trout. FISH TRANSPORT SYSTEMS