1. Recirculating Aquaculture Systems

2. 2 Recirculating aquaculture systems (RAS) are systems in which aquatic organisms are cultured in water which is serially reconditioned and reused.

3. 3 Why recirculate?  Conserves water  Permits high density culture in locations where space and or water are limiting  Minimizes volume of effluent, facilitating waste recovery  Allows for increased control over the culture environment, especially indoors  Improved biosecurity  Environmentally sustainable

4. 4 Water Reuse Rates Open or Flow-through System Closed System 0%100%50%25%75% Semi- Closed System

5. 5 Characteristics of Culture Tank Effluent  High concentrations of suspended and dissolved solids  High ammonia levels  High concentration of CO 2  Low levels of dissolved oxygen

6. 6 Recirculating System Applications  Broodstock maturation  Larval rearing systems  Nursery systems  Nutrition and health research systems  Short-term holding systems  Ornamental and display tanks  High density grow out of food fish

7. 7 Scientific Hatcheries Huntington Beach, California

8. 8

9. 9 Seagreen Tilapia Palm Springs, California

10. 10 Seagreen Tilapia Palm Springs, California

11. 11 Kent SeaTech Southern California

12. 12 Kent SeaTech Palm Springs, California

13. 13 Southern Farm Tilapia Raleigh, North Carolina

14. 14 Southern Farm Tilapia Raleigh, North Carolina

15. 15 Mote Marine Lab Sarasota, FL

16. 16 Mote Marine Lab Sarasota, FL

17. 17 Harbor Branch Shrimp Fort Pierce, Florida

18. 18 Harbor Branch Shrimp Fort Pierce, Florida

19. 19 Classification of Culture Systems  Trophic Level  Temperature  Salinity

20. 20 Questions for you  Definitions: a. Define - Trophic Level b. Define - Salinity c. Explain this system - Larval rearing systems d. Define – Oligotrophic e. Define – Mesotrophic f. Define - Eutrophic

21. 21 Classification of Culture Systems Recirculating Systems Freshwater Marine Warmwater Coldwater Oligotrophic Mesotrophic Eutrophic Oligotrophic Mesotrophic Eutrophic Oligotrophic Mesotrophic Eutrophic Oligotrophic Mesotrophic Eutrophic Examples Tropical Rainforest Tropical Display & Breeding Warmwater growout Hardy warmwater Salmonid spawning Coldwater growout Null Marine reef Marine growout Null Coldwater aquaria Coldwater growout Null

22. 22 Salinity Major effect on the oxygen saturation level Freshwater Less than 10 ppt Marine Greater than 10 ppt

23. 23 Temperature Impacts the rates of chemical and biological process at the most fundamental level Affects: bacterial growth, respiration, nitrification efficiency Cool-water species: below 20º C Warm-water species: above 20º C

24. 24 Trophic Level Distinguishes the level of nutrient enrichment Oligotrophic Mesotrophic Eutrophic

25. 25 Oligotrophic  Excellent water quality  Very Clear  Used in display aquaria  Most frequently used for breeding purposes  Some species are kept in these conditions all of their lives, while others for a period of time

26. 26 Mesotrophic Describes the bulk of high-density production systems where risk and economics must be carefully balanced to achieve profitability  Some deterioration in aesthetics  Water quality at safe levels  Dissolved Oxygen- above 5 mg/L  TAN & Nitrite – less than 1mg-N/L  Total suspended solids – less than 15 mg/L

27. 27 Eutrophic Exist for the grow out of the most tolerant species that show vigorous growth under moderately deteriorated water quality conditions  Dissolved oxygen levels- economic optimum level  Ammonia & Nitrite – less than 2mg-N/L  Water quality – marginal  Species evolved under similar natural conditions prosper in these conditions

28. 28 Integrated Treatment An assembly of components that creates an artificial environment suitable for production, breeding or display of aquatic animals Must be reliable Must be cost effective Must be compatible with the intended user group

29. Fine & Dissolved Solids Removal Solids Capture Waste Mgmt Biofiltration & Nitrification Hydraulics CO 2 Removal Water Quality, Loading, Culture Units, Species Aeration & Oxygenation Disinfection & Sterilization System Components System Control

30. 30 Your work - 1. Why would Disinfection & Sterilization be an important function of your Aquaculture system? 2. In our system we have Biofiltration & Nitrification. In your own words why would this be an important function of our Aquaculture system? 3. In our system please explain how Aeration & Oxygenation works to purify the system.

31. System Design & Construction Monitoring & System Control Economics Biosecurity Nutrition Management Decisions

32. Water Quality, Loading, Culture Units, Species System Components

33. Circular Tank Flow Pattern

34. 34 Alternative Drainage Strategies Two Drains

35. 35 Dual Drains Cornell Dual-Drain Design Tank depth - 1.0 m Tank diameter - 3.0 m Tank volume - 7.4 m 3

36. 36 Commercial Dual Drains Aqua Optimas Aquatic EcoSystems

37. Raceway - Plug Flow

38. Racetrack Configuration

39. Fine & Dissolved Solids Removal Solids Capture Waste Mgmt Water Quality, Loading, Culture Units, Species System Components

40. 100 75 50 30 10 Course Screen Sedimentation Tube Settler Microscreens Granular Filter Foam Fractionation Particle Size in an Intensive Aquaculture System DE or Cartridge Filter PRETREATMENTMAIN TREATMENTPOLISHING TREATMENT (After Chen & Malone, 1991)

41. 41 Sludge Removal INFLOW OUTFLOW Sludge Removal Tube Settler Settling Media

42. Tube Settler

43. 43 Oligotrophic Lacking in plant nutrients such as phosphates, nitrates, and organic matter, and consequently having few plants and a large amount of dissolved oxygen throughout. Used of a lake, pond, or stream. Compare dystrophic, eutrophic.

44. 44 a.Mesotrophic of a body of water : having a moderate amount of dissolved nutrients

45. 45 eutrophication - the process by which a body of water becomes enriched in dissolved nutrients (as phosphates) that stimulate the growth of aquatic plant life usually resulting in the depletion of dissolved oxygen