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Raceways
Introduction
• Raceways are considered flow-through
systems.
• Beging simple to construct they are some of
the oldest designs in aquaculture.
• Water sources for raceway aquaculture
operations are usually streams, springs,
reservoirs or deep wells.
What materials?
• What do you need to make a raceway?
• In today’s market...lots of concrete!
How long?
• Length x width of 6:1 is recommended.
• This prevents the fish stock from swimming in
circular movements, which would cause debris
to build up in the center.
• If the width is too large this could result in a
feeble current speed which is not desirable
(see below).
• Length is usually constrained by the water
quality or stocking density.
How deep?
• Average depth of a raceway for fin fish, such
as rainbow trout, is about three feet.
• This means each section in a raceway should
be about 90 ft long and 6-9 ft wide.
• A slope of 1-2% doesn’t hurt either!
How many fish?
• For trout, stocking rates of 30 to 50 kg/m3 are
normal at the end of a rearing cycle!
• While for marine species, such as sea-bass and
sea-bream, the achievable load is lower,
between 15 and 20 kg/m3.
• Raceway volume required = total amount of
fish in kg/stocking rate in kg per m3.