RAS (Recirculation Aquaculture System)
The Recirculation Aquaculture System, or RAS, is based on the intensive production of marine species by reusing water multiple times after treatment and renewal. This primary feature reduces the amount of water used per production cycle and allows for farming in locations that were previously not possible. In Chile, RAS cultivation of Atlantic salmon (Salmo salar) is primarily focused on rearing fish until the smolt stage, and more recently, post-smolt. Currently, RAS systems for salmon production worldwide cover the entire production cycle and have diversified into the production of other species. Some advantages of this type of farming include optimized waste management and nutrient recycling, which reduce the impact on both freshwater and marine environments, the reduction of emerging pathogenic diseases and the shortening of farming cycles in the sea.
Open Flow
Open flow farming refers to a salmon farming system that relies on natural water sources for its operation. In Chile, it is one of the most commonly used farming systems and involves the rearing of salmon during their freshwater life stage, from eggs and first feeding until smoltification. This system encompasses the smoltification stage, where the fish must be in optimal osmoregulatory conditions for their transition to seawater. The freshwater phase is crucial as the optimal farming of fish during this stage has a significant impact on health and productivity during the subsequent grow-out phase in the sea.
Sea grow-out
The sea grow-out phase is the final stage of Atlantic salmon and Coho salmon farming. During this period, the fish are kept in cages in the sea for approximately 14 to 16 months and interact with the marine environment, including currents, temperature and salinity. They express their growth potential based on factors such as feeding, genetics, welfare and health.
Once the fish reach the appropriate weights, the grow-out stage concludes, and they are harvested and sold to their target markets.
