By Llyn Aquaculture Ltd

1. Recirculation Systems for fish and
shrimp with integrated hydroponics
(Aquaponics)
Recirculating Aquaculture Systems - RAS
• Candidate Species
• System Design and function
• Snippets of economics (dangerous without looking at all
details of each situation)
• Possibilities to integrate with hydroponics
• Aquaponics – Fish farming with a bit of veg’ on the side

2. Llyn Aquaculture Ltd
 Established Summer 1999 at Afonwen
Farm, Pwllheli, Gwynedd, N. Wales
 Marine and Freshwater Recirculation
Systems
 Demonstration Farm
 Design and Consultancy
 Supply and installation
 R & D projects

3. Recirculation Systems – Llyn Aqua
 Marine systems
 Brackish water Turbot pilot system - Marine
 Fresh water

4. Llyn Aqua Pilot System.

5. Design and supply Intensive Fish Production
systems – research, pilot and commercial.
 High Value species
 Turbot
 Sole
 Shrimp
 Sea Bass
 Eels
 Fresh water Perch
 Arctic Charr
•Low Value (high
volume)
•Barramundi (Asian Sea Bass)
•Tilapia

6. General Design Considerations
Choice of Species
Temperature Production capaci
Location Water Issues
Availability / discharge
Biosecurity
Design
Financial Issues
Salinity Grants
Investement
Sales stratedgy Selling price
Production costs
Construction costs
Land cost
Borrowing cost

7. Reasons to Recirculate
 Limited Water
 Temperature Control
 Salinity Control (specialised)
 Disease control
 Increase production per unit area / volume
 To boldly grow fish where no fish has been grown
before

8. Recirculation System Complexity vs % daily
exchange
% of tank volume exchanged per day
2,400% 1,000 % 500% 100% 50% 20% 10% 5%
Mechanical Filtration
Flow Through Re - Use Biological Filtration
Oxygen + Aeration Fine Filtration (< 50 micron)
UV
Simple Solids Separation Degassing and pH control
Sedimentation
Foam Fractionation
Denitrification
Ozone

9. Design. Each situation is unique and
must have custom design based on tried
and tested technology.
 Water Exchange (new water)
 Mechanical Filtration – Coarse and fine particle removal
 Biological Filtration
 UV and Ozone
 Gas Exchange / Oxygen / CO2 /pH
 Salinity
 Water Movement – pumping and pipes
 Protein skimming / foam fractionation

10. Reduced water exchange to < 50%
vol per day
 Fine particle filtration (< 50 micron) – side
stream
 UV ‘sterilisation’ – side stream
 Foam fractionation (Protein skimming)
 Ozonation – requires strict control – only to
be used on very ‘closed’ intensive systems.
 pH Buffering

11. Pros and Cons - Recirculation
 Total Control
Cons
 Water Quality
 High Cost!?
 Temperature
 Oxygen More Pros
 Flow rates •Enables aquaculture to
 Disease Control take place where otherwise
not possible
 High Productivity
•Low food miles
 Low Labour •Freshness
 Effluent Control

12. E.g. Recirc’ vs Flow Through with 5
m3/hr water (120 m3/day)
 Flow through – 10 m3 tank vol – 1 tpa
production
 Recirculation 10 % volume exchanged per
day – 1,200m3 tank vol – 120 to 200 tpa
production depending on species.

13. Minimal Water intake
e.g. 20 tonnes Sea Bass pa
Fine Filtration – 5 micron
High UV dose - Filter and
UV rated 4m3/hr – used at –
10 m3 per day.
Pathogen Free
Pumping once per month
from sea to storage tank.
Easy temperature control

14. Species – with system examples
 Marine (or Fresh Water (or Brackish)
Brackish)
Arctic Charr
 Turbot
 Sea Bass Perch
 Sole
 Shrimp
Barramundi
 Barramundi Tilapia
 Sea Trout
 Halibut (cold) Sturgeon

15. 2000 – 2002, 1st sea bass RAS in UK, 20
tonnes per annum (300m2 building)
Purging tank (clean
water)
Total water volume of 160 m3 = 125 Kg / m3 / yr
Water Exchange average 10% / day = < 300 l/ kg fish

16. Sea Bass
•Temperature (opt) 18-25
•Salinity 10-40
•Growth to 400g <1 yr
•Growth to 800g Av’ 1.5 yr
•FCR 1.3 to 1.5
•Density - up to 100 Kg/m3
Pros Cons
•Temperature •Delicate
• Well known •Aggressive
• Sales volume •Competition
•Fry •Low price
•£4.50 / Kg
•Large volume

17. Ongrowing System. Sea Bass 160 Cubic metres.-
Llyn Aqua Pilot - 20 tonnes per year = 125 Kg / m3
per year!
Price Drop
00-02 - £5.5 to £6.5/ kg ex farm
03 < £4.50 delivered UK from Greece
2009 – Euro 3.00 per Kg (Greece, Turkey)
Now need to sell at £4.00 to £4.70 per Kg ex
farm UK

18. Turbot and Dover Sole

19. 200 m3 / hr filter in 25
400 m3/ hr filter in 60 tonne per annum perch unit.
tonne pa charr unit Note purge tanks behind.

20. •Turbot Ongrowing.
Low energy
Low volume shallow
tanks
Low FCR.
0.8 up to 1 Kg
1.0 up to 1.5 Kg

21. Turbot. 1.5 - 2.0 Kg in 18 - 24 months
from egg. 12 – 18 moths from 5-10g fry
Pros
•Temperature (opt) to 500g 22 to17
•Temperature*
•Temp’ (opt) 0.5 – 2Kg 17 to14
• Luxury Niche
•Salinity 10-37
•High Value
•Growth to 1 kg 1 to 1.5 yr
£6.0 - £7 per
•Growth to 1.5 Kg 18 – 24 mths Kg
•FCR 0.9 to 1.1 •Higher if sell
direct
•Density - up to 40 Kg/m2
•At 30 to 40 cm deep = 100-120kg/m3

22. Turbot Shallow Raceway system

23. Turbot in Shallow raceway recirculation system. 20
Kg per m2 (7 cm deep) = 285 Kg / m3
Approx’ 600 kg / m3 / year production !
At 10% exchange per day
= 60 litres per Kg
produced.
(Sea bass = 300 l/kg)

24. Solids Removal
 Prevents overloading of bio-filter and build up of
anoxic sludge.
Removal down to 50 microns.
 Sedimentation – Simple / low flow / load
 Moving screens – Drum or Conveyor belt
Removal below 50 microns
 Fixed bed – Pressurised sand or beads
 Fixed bed – slow up-flow / submerged media
 Both require periodic backwashing.

25. Example 50 tonne perch farm – Ireland, 2 modules of 25
tonnes per annum
47.500m
Upflow
Upflow
1.800m
1.800m
4.000m
2.950m 0.400m 2.950m
4.000m
3.600m
3.600m
RSJ
RSJ
0.800m 0.800m
2.250m 2.250m
3.850m 3.850m
Fluid Bed
Fluid Bed
2.800m
2.800m
1.850m 1.850m
12.000m
Concrete drain sumps
6.000m
1.900m
1.900m
0.800m 0.800m
6.000m 6.021m
6.021m 0.150m 0.150m 8.500m
2.000m 2.000m
1.936m 1.936m 200mm 85
m
1.500m
UV
1.500m
UV
0.5
m
Water filtration area
2.650m 2.650m
m
00
35
.5
0.3 85
0.2
m
0.3
0.2
00
4.000m
m
35
m
3.850m 3.850m
4.000m
2.760m
Pink pipes above ground until this point 160mm pipe under tanks Waste pipe between the two 400 mm pipes here
Green pipe shows waste water out from sumps

26. Solids removal – Moving mesh with
backwash spray - Conveyor or Drum filter.

27. Drum Filter – High flow / low head
Only 2 – to 5 cm head loss

28. Mechanical Drum Filter with vortex
separator Biological Filtration
1.800m
4.000m
2.950m
3.600m
0.800m
2.250m
3.850m
2.800m
1.850m
6.000m
1.900m
0.800m
6.021m
0.150m
2.000m
8.500m
1.936m m
85
UV
1.500m
0.5
2.650m
m
35
0.2
0.3
00
m
3.850m
4.000m
2.760m
Low Head Pumps
Biological Filtration

29. 30 tonne per annum system (European Perch) Low Head Llyn
Aqua pumps- 6 of 100 m3/ hr @ 1m head. 0.75 KW each.

30. Trickle Filter & Low Head (1 to 1.5m) Axial Flow
pumps

31. (pre 2000 technology) 8 + 2
temp monitoring.
£9,000 in 1999
Llyn Aqua Sensor Monitor (LASM)
e.g 8 oxygen - £4,000 Today

32. Monitoring and control -
4 x LASM units on
network – with phone
dialer
•2 x 25 tonne systems -
•24 Oxygen
•2 Temp
•6 float switch level alarm
•2 pressure switch – Oxygen
•Power failure
•WWW – viewed and
controlled from anywhere on
net

33. Dover Sole – The Holy Grail?  Very High Value
 Very difficult broodstock
 Slow Growth – 300 –
400g in 1 year (30% of
stock)
 Feed related – Do not
thrive on fish based diet

34. Stacked Shallow
Raceways

35. • Temperature (opt)
12-17
Arctic Charr • Salinity 0 - 37
• Growth to 1Kg <1 yr
Fresh water – brackish - marine • Growth to 1.5Kg 17 mth
• FCR <1.0
• Density - up to 100
Kg/m3
Down Side
Price drop
2006 £5.30
2009 Euro £4.50
Production cost of
£3.5 / Kg.
£3.0 / Kg at over
200 tonnes.

36. Relevant Example - 60 tpa Arctic
Charr farm - Ireland.
 Bore hole water - 12 Deg. C
 50 % exchange per day (300m3)
 Circulation up to 2.5 x per hour through
tanks = 60 times per day
 New water = 0.8 % per cycle
 Rate of recycling = 99.2%

37. 60 Tonne per annum Charr.
Nursery system – 8 of 15 m3
Grow Out System – 4 of 100
m3
Fish More relaxed at high density
– up to 80 Kg/m3 in Nursery and
100 Kg / m3 in Grow out tanks –
10 tonnes per tank!

38. Large tanks – more economical from Concrete. < 10 m3,
GRP or HDPE.

39. •Halibut Raceways – Norway
•Flow Through farm
•Failed due to disease

40. Total Flow 1000 m3 / hr

41. Crystal clear purging system – 1 week prior to
slaughter. Empty guts and remove any ‘off flavour’

42. Low visual Impact - no more than mushroom farm.

43. Fresh Water European Perch.
•Temperature (opt) 18-25
•Salinity 0 - 10
•Growth to 200g 10 mths
•Growth to 400g Av’ 12 - 18
•FCR 1.3 to 1.5
•Density - over 100 Kg/m3
•Very Niche market - Switzerland

44. Concrete block – 50 Tonne
Perch, Ireland

45. Tropical Shrimp (white)
L. Vannamei
•Temperature (opt) 26 - 30
•Salinity 3 - 40
•Growth to 20g 4.5 mths
•£8 (20g) to £12 (25 – 30g) / Kg
•FCR 1.0 to 1.3
•Density - 7 to 10 Kg/m2
•Niche market – top quality,
never frozen, super fresh,
live, no preservatives,
harvest and deliver same day.
•Not to compete with bulk
frozen imported

46. Super Intensive
‘ICE’ (Indoor
Controlled
Environment)
shrimp
Up to 8 Kg / m3
28 Deg C
25 Kg / m2 / yr output
Salinity 5 to 40 ppt

47. ‘ICE’ Shrimp – Indoor
Controlled Environment
PROS
•Fast turnover
•2.5 cycles per year
•25 Kg / m2 tank per year
•High price - £8 + /kg ex farm
CONS
•High space required
•High Temp
•Cheap competition
High space means high
construction cost – 100
tonnes - £1.25 million

48. Tilapia – The Chicken
of the ‘sea’
PROS
•Fast turnover (<10 mths)
•>200 Kg / m3 / year
•Salinity 0- 5ppt
•Some strains – full Sea water
•Low protein plant based feed –
35%
•Production cost ca. £4.0/Kg
400 tpa farm – ca £1.45m
CONS
•High Temp 26 - 30
•Cheap competition

49. Tilapia competition < £1.0 / Kg

50. Aquaponics -Plenty of freshwater
examples on the internet
 Silver Carp +
Rice
 ‘Backyard’
aquaponics

51. Llyn Aqua Integrated System – 2001, EU
funded R & D programme - GENESIS
Lly Aquaculture - C C
old limate Integrated System
F R
ish earing Systems Surplus water
W W
aste ater+ Sinking
Sludge Secondary Settler
Primary S ettler
Floating
Solids separation
Septic tank
Discharge
C 5 m3 per day
a.
Phytoplankton / A ??
rtemia T N
o atural Wetland
or recycled back to fish
New 10.000m
3.000m
Sedimentation, worms?
300m3 40 m3 300m3
12.000m
P eriodic pumping 2m deep 0.3m deep 2m deep
Spread on Land R = 4 days
T
10.000m
Aerated Lagoon
Retention time
30 days
Phytoplankton Salicornia + Clams ?
3.032m
N A
ew rea
S G ??
and ravel w simulated tide
ith

52. Nutrient Assimilation - Clean
discharge.

53. Mean water quality During May
May Water Quality (Mean of Weekly samples)
0.6 14
ppm Phos & Ammonia
ppm Nitrite & Nitrate
0.5 12
0.4 10
8
0.3
6
0.2
4
0.1 2
0 0
2 3 4 5 6
Nitrite 0.28 0.001 0 0 0
Nitrate 0.55 0.12 0 0.05 0.03
Ammonia 8.3 2 1.8 1.1 0.5
Phosphate 11.6 10.6 5 8.1 6.1
Position

54. Manila (Sept) Native (Sept)

55. Phytoplankton
 Euglena Spp.
 High Nutrient -
Brackish

56. Phytoplankton
 Prasinophyte
 Platymonas Spp.??)

57. Rotifer Population Density
Rotifer density 2003 / 2004
140
120
100
Pos' 3
Pos' 4
80
Pos' 5
Pos' 6
60
Harvest - m
Pos 5. 2004
40
20
0
08/04/2003
22/04/2003
06/05/2003
20/05/2003
03/06/2003
17/06/2003

58. Manila Clams Native Clams

59. Early
Salicornia
(Samphire)
trials

60. Salicornia – Species selection,
development of ‘strain’, and seed
production.

61. Replicated density trials
Up to 10 Kg / m2 per
year
Wholesale - £5 per Kg

65. Western Australia. Barramundi and
peppers.

66. Abalone - Fish/shrimp - plankton

67. Abalone - Shrimp - Sea Weed
(Ulva)

68. Israel: Integrated System
Algae grown in discharge
water from recirculation
system
Used as feed for
Abalone and
Urchins

69. Bore hole sea Israeli Integrated model Algae
water Abalone + Urchins
Algae as
feed for
Abalone
Nutrient
rich water
Salicornia beds
Intensive
sea bream
RAS