Recirculating aquaculture (RAS): frequently asked questions
Quick answer
A recirculating aquaculture system (RAS) is a land-based fish farm that cleans and reuses most of its water through mechanical and biological filtration, degassing, oxygenation and disinfection, allowing high production with close control.
How a RAS works
- Mechanical filtration removes solids
- Biofilter converts ammonia to nitrate
- Degassing removes carbon dioxide
- Oxygen is added
- UV or ozone disinfects the water
- Clean water returns to the tanks
Where to go next
Read our detailed guides on planning, site selection, costs and supplier comparison, or use the calculators to estimate your project.
Frequently asked questions
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