Recirculating Aquaculture System (RAS)

  • Re-circulating aquaculture systems are indoor, tank-based systems in which fish are grown at high density under controlled environmental conditions.
  • These systems can be used where a land area or water is limited, or where environmental conditions are not ideal for the species being cultured.
  • This type of aquaculture production system can also be practiced in marine environments.
  • A tremendous increase in population with a direct proportion in demand for protein-rich food. The higher cost of protein-rich food in the country is due to higher demand and limited supply.
  • High Pollution in ponds, rivers, and lakes & High concentration of ammonia causes lethal stress to fish.
  • Recirculatory aquaculture systems (RAS) are systems in which aquatic organisms are cultured in water that is serially reconditioned and reused.
  • It also conserves water.
  • Permit high-density culture in locations where space and water are limiting.
  • Minimizes water of effluent, facilitating waste recovery
  • Allows for increased control over the cultural environment especially indoors.
  • Improved biosecurity
  • Environmentally sustainable.

A recirculatory aquaculture model is a closed system. It combines fish tanks, filtration, and water treatment systems. The fish are housed in tanks and therefore the water is exchanged continuously which guarantees and consists of optimum growing conditions.

Water flows by pumping out into the tanks, through biological and mechanical filteration systems then returned into the tanks. Therefore, no complete water exchange, rather only 5% to 10% water rate of exchange takes per day is being done.

Recirculating the aquaculture system is the key to the future of aquaculture. Its merits outweight its disadvantages.

  • It makes sustainable use of the water resources, and in places where there is a scarcity of good quality water.
  • Even though it has a high establishment cost, the scope of RAS is vast, it is environment friendly, there is control over the production, and the supply can meet the demand according to the market conditions.
  • There is low pollution to the surroundings in Recirculating aquaculture system.


Better FCR

High Yield

Less Labour

1. Tanks

Tanks are usually utilized for 

2. Drum Filter

3. Bio Filter

4. Degassing

5. Oxygenation

6. UV Treatment

7. Monitoring

Want to Know More About RAS Fish Farming System.

We have seen many good days and bad days in RAS Fish Farming, and we learnt a lot from them. We are sure that all our experiences will help you do RAS Fish Farming easy peasy.