Recirculation aquaculture systems (RAS) have built-in water treatment systems. After the water treatment process the clean water flows back into the fishpond. Water use is in these systems is generally low. Production factors as temperature, feed, oxygen and pH can be optimised in a closed system. There is no risk of escapements and diseases cannot be transferred to wild populations. Use of chemicals and antibiotics is almost zero.
The benefits of a RAS are full control of the production process and environmental friendly production, as discharge water is treated and reused.