The design and management of tanks for the culture of turbot (Scophthalmus maximus (L.))
Abstract
The culture of turbot Scophthalmus maximus is currently
conducted only in tanks, unlike many pelagic species which
are also grown in net cages. Despite the demersal habit
of this species, deep pelagic fish tanks are often used
with little or no adaptations.
A multidisciplinary study was conducted to establish the
consequences of several management regimes, primarily a
decrease in water depth, on more than a total of 40
biological, water quality and hydrodynamic parameters.
Fish fitness, performance and behaviour, exit age
distribution, flow visualization, flow velocity
determination and water quality determination studies were
conducted.
Results were discussed in relation to optimal tank
management strategies, suitable tank designs, or
adaptations to existing designs. A statistical model was
proposed. A decrease in water depth from 18 - 9 cm
decreased dead volumes from 6.95 - 1.37 1. An increase in
depth from 3 - 18 cm increased turbot specific growth
rate by 0.44 % day-1 . Tank hydrodynamics had little
influence on biological or water quality parameters,
despite the large range of water depths relative to the
size of the tanks. It was more probable that stocking
density and biomass were the major influences on water
quality and this in turn may have influenced fish
performance. The advantages of reducing water depth in a
culture tank were more numerous than the disadvantages.