Raceway Tank
mercial recirculating systems. RAS
systems can, with clever engineering, be designed in a way where
different height levels and gravitation flow is used to the best to limit
energy requirements. Good insulation and appropriate building materials can also help to keep the environment at the best possible temperature for the culture species of
choice. From a variable cost (feed,
fingerlings, electricity, and labour
cost) standpoint, the cost of producing fish in recirculating systems
is not that much different from other production methods. Feed cost is
an area in which recirculating systems can actually have an advantage. Tank production systems
generally can produce a better feed
conversion ratio than pond systems.
Comparing the production capacity
Trout Ova Incubator
per Rand invested in recirculating
production systems with other fish
production methods is critical to
making an informed economic evaluation. It will make better business
sense to try and produce higher
value fish species in RAS facilities
compared to lower value species.
For instance if you have a huge capital layout for a RAS facility it would
make more sense to produce Atlantic Salmon with a high market value
compared to Common Carp with a
low market value.
Conclusion:
What all RAS systems share, is their
ability to separate the culture of
fish from the natural environment,
control their inputs to reduce diseases, optimize growth and minimize mortality, and control their
outputs to limit external costs to
Sturgeon Broodstock
UV Light
the environment.
At this juncture in the evolution of
aquaculture, considerable debate
remains as to the adaptability of
RAS systems to the range of commodity fish species. Technological
advancements, regulatory developments and the selection of species
will continue to intermingle over
the coming years. Local variables
such as climate, water availability,
alternative energies, access, socioeconomic conditions, amongst others, will help determine the local
suitability of Recirculating Aquaculture Technology.
Trout Hatchery