Raceways aquaculture Introduction Raceways are considered flowthrough systems

Raceways aquaculture

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.

Raceways

Raceways • Yield – 15 -20, 000 lbs for every 500 gallon/min flow. Concrete Raceway Earthen Raceway

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/m 3 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/m 3. • Raceway volume required = total amount of fish in kg/stocking rate in kg per m 3.