The document summarizes the design of an aquaponic system by Lydia Wayua. It introduces aquaponics as a system that combines fish farming and hydroponic crop production without soil. The design objectives were to evaluate suitable systems for a farmer in Kamulu, Nairobi, and to design fish tanks, a hydroponic system, and a water recirculation system. The selected design incorporated circular fish tanks, settling and filter tanks, a vertical tower hydroponic system, and components for pumping and piping water. The concluded that the designed system could produce an estimated annual yield.

1. UNIVERSITY OF NAIROBI
DEPARTMENT OF ENVIRONMENTAL AND BIOSYSTEMS ENGINEERING
FEB 540: ENGINEERING PROJECT ORAL EXAMINATION
2014/2015 ACADEMIC YEAR
PROJECT TITLE: DESIGN OF AN AQUAPONIC SYSTEM
BY: WAMBUA LYDIA WAYUA
REG NO. F21/1731/2012
SUPERVISOR: MR. S.C. ONDIEKI
8TH May 2015

2. INTRODUCTION: DID YOU KNOW…?
 1. Fish water is loaded with nutrients?
 2. Crops can grow to their maximum potential
using fish water as they would in well fertilized
soil?
 3. Crops can grow without soil?

3. GROWING WITHOUT SOIL (HYDROPONICS)

4. FISH WATER: INTENSIVE FISH FARMING

5. DEFINITION: AQUAPONIC SYSTEM
 Aquaponics is the marriage of intensive modern fish farming
in tanks to intensive modern hydroponic farming.
 Hydroponic farming:
 “Hydro” –water, “Ponos”- working.
 It is the art of growing crops in sand, gravel or liquid with
added nutrients without soil.
 Main crops grown in hydroponics: local vegetables, tomatoes,
strawberries, lettuce, cucumber, peppers as well as ornamental
crops such as herbs, roses and foliage plants.
 Main fish type kept: tilapia, cat fish, Nile perch e.t.c

6. LITERATURE REVIEW: PIONEERS IN
AQUAPONICS
 The pioneer of aquaponic system was in USA, at the
University of Virgin Islands.
 The system was developed in the 1970s and has been
operational commercially since then.

7. LITERATURE REVIEW CONT…
 Interest is expanding in sustainable agriculture and producing food
closer to urban centers, stimulating involvement from a small but
growing aquaponics industry.
 This technology is slowly being adopted in Kenya .
 Hydroponics, in Kenya :Mr. Chege Peter from Zambezi area in
Kikuyu and the nutrient solution is named ‘hydropeter’.
 An aquaponic farm has been operational in Kinangop by Mr. Daniel
Kimani

8. LITERATURE REVIEW: COMPONENTS OF THE
SYSTEM

9. DID YOU KNOW…?
 1. Aquaponics can grow 90% more food on 90%
less space?

10. PROBLEM STATEMENT
Problem statement
 Addresses two major issues;
 (1) The issue of limited land
 (2) Low yields
Hypothesis
 An aquaponic system can grow 90% more food on 90%
less land.

11. OVERALL OBJECTIVE
 To design a system that integrates crop and fish farming
for a potential farmer in Kamulu area, Nairobi.


12. SPECIFIC OBJECTIVES
1. Evaluate and select the most suitable design alternative
2. Design of:
a) A strawberry hydroponic system
b) fish tanks and a sump.
c) Mechanical filtration devices
d) Biofilter
d) A water recirculating system: pumps, piping, and
fittings

13. GENERATION OF CONCEPT DESIGN
FUNCTIONAL DECOMPOSITION METHOD

14. GENERATION OF ALTERNATIVE DESIGNS

15. HYDROPONIC ALTERNATIVES

16. HYDROPONIC ALTERNATIVES

17. EVALUATION & SELECTION OF DESIGN
 Decision matrix was used for evaluation

18. MOST SUITABLE SELECTION
 Selected components are:
 Fish tank………………………...circular fish tank
 Settable solids removal…………settling basin
 Suspended solids removal………filter tank
 Hydroponic system…………......vertical tower configuration
 Pump………………………........centrifugal type

19. PRODUCT DESIGN: DESIGN STEPS
 1. Design of a vertical strawberry farming system
 Farm dimensions
 The farm dimensions were measured with a tape measure and
the elevation profile obtained using a GPS and Google earth.
 Number of towers (Zipgrow, 2014)
Number of crops per tower (Zipgrow, 2014)
 .

22. DESIGN CONT…
2. Calculation of the fish tanks volume
fish rearing area ratio 1 ft3 of fish rearing to 2 ft3 of
media, (Rakocy, Masser and Losordo, 2006)
critical standing crop, a value of 0.5 pounds per
gallon recommended fish density

23. DESIGN CONT…
3. Calculation of the flow rate
 The system flow rate was calculated using the
empirical formula:

24. DESIGN CONT…
4. Design of the inlet and outlet water structures for the fish tanks.

25. DESIGN CONT…
5. Design of the settling basins.

26. DESIGN CONT…SEDIMENTATION BASIN

27. DESIGN CONT…
6. Design of the piping network.
 fluid flow continuity equation Q = AV
 From which,
 A=Q/V
 A=∏r2; r = ; d=2r, where d is the pipe diameter.

 The head loss in the pipes is determined as:
 hf =

28. DESIGN CONT…
 Selection of a suitable pump for the system
 Calculation of system head:
pump power requirement will be obtained using the
equation:

29. SYSTEM LAYOUT

30. RESULTS

31. CONCLUSION: ESTIMATED ANNUAL PRODUCTION
FROM THE DESIGNED SYSTEM.

32. RECOMMENDATIONS
 Solar power harnessing
 Rain water harvesting

33. REFERENCES
 LOSORDO.T.M, MASSER.M.P and RAKOCY.J, (1998),
Recirculating Aquaculture Tank Production System: An
overview of critical considerations, SRAC Publication No. 451,
New York
 MALONE .R. (2013), Recirculating Aquaculture Tank
Production System: A review of current design practice, Southern
Regional Aquaculture Centre (SRAC) Publication No. 453
 MASSER .M.P, RAKOCY.J and LOSORDO .T.M, (1999),
Recirculating Aquaculture Tank Production System:
Management of Recirculating Systems, SRAC Publication No. 452,
New York

34. THE END
THANK YOU

35. EXTRA SLIDES

36. COST-BENEFIT ANALYSIS

37. SITE ANALYSIS
 Tilapia thrive in the temperature range of 21.11° C to
29.44° C while the recommended temperature for
strawberries is 15-30°C. Thus these two fall exactly
within the temperature range in Kamulu.
 electricity supply to the area
 Strawberries require maximum sunlight exposure

38. BILL OF QUANTITIES