THE HANGING

GARDENS OF

HWA CHONGGroup No.: 12-25

Keven Loo Yuquan 4I106 (L)Ching Kai Xiang 4I202Fong Hok Shing 4I204

Koh Qian Siang, Gordon 4I208

Implementation Process: Part a1

Test Phase 1Aim:- To estimate the amount of nutrient

solution required in the entire system- To determine the volume capacity of the

plant trays- All these will help us to specify the

benchmark for replenishing lost solution into the system.

Implementation Process: Part a2

Procedure:We compared the difference in water level before and after the pump was turned on. When the final reading was taken, the trays were filled and there was constant drainage.

Implementation Process: Part a3

The MathInitial volume of water = πr2h

= (29.5)2 x 56 x 3.14 = 153L (3sf)Final volume of water = (29.5)2 x 26 x 3.14 = 71L (3sf)Total volume of plant trays = 153L – 71L

= ~82L

Implementation Process: Part a4

Analysis- Our system requires a substantial amount

of solution to run.

Follow-up- We have decided to refill the solution when

the water level drops in the water tank drops below 40L (at a depth of 15cm).

Implementation Process: Part b1

Test Phase 2Aim:- To investigate if the system would continue running

even after a long period of use- To check if the system would create regions of stagnant

water that would allow mosquito breeding- To estimate the water loss of the system by evaporation

Procedure:- We left the system on with the pump running for several consecutive days

Implementation Process: Part b2

Results:- The system with water remained running after six

days with no water flow problem.- When we inspected the water, there was no

evidence of stagnant water pools or mosquito larvae.

Analysis/Follow-up- Constantly-moving water eliminates threat of

mosquito breeding by preventing stagnant water from accumulating.

- Success. None required.

Implementation Process: Part c1

Test Phase 3Aim:- To investigate the efficiency of our solution

design in the growth and yield of crops.

Procedure:- We transplanted batches of 小白菜 seedlings

into the system and observed the changes and health of the seedlings over a period of time.

Implementation Process: Part c2

Results (1st batch of seedlings): - The seedlings died after two days, due to a

unnoticed fungus infection.

Analysis/Follow-up- Seedlings are very prone to “damping off”, caused

by a fungus infection that results in weak spiny stems and the rotting of the roots, thus slowly killing the seedling.

- We cleaned the system and made sure that the next batch of seedlings would not be contaminated.

Implementation Process: Part c3

Results (2nd batch of seedlings): - More than four-fifths wilted after five days, due to

other problems which did not have enough time to surface during the 1st batch of seedlings.

Analysis- There was too much water for seedling growth.- This also contributed to higher levels of water

wastage, and could lead to the problem of root rot.- Furthermore, the lack of a growth medium meant

the plants had a lacked anchorage for the roots.

Implementation Process: Part c4

2nd Batch of Seedlings: Most have wilted

Implementation Process: Part c5

Follow-up- We lowered the water levels in each tray to a more

suitable level.- We also introduced leca into all the trays.

Benefits of using leca include:• Has high absorbance capacity• Reduces amount of water needed for system• Provides anchorage for plants• Allows for growth of microbes and bacteria that

supports plant growth (mutualism).

Implementation Process: Part c6

Results (3rd batch of seedlings): - We are in the midst of growing our 3rd batch of

seedlings.- As of now, the seedlings look healthy and are

growing.

Follow-up- Due to the addition of leca, we had to cover the

opening of the connecting pipes with wire netting to prevent leca from falling into it and choking the water flow.

Implementation Process: Part c7

3rd Batch of Seedlings

Implementation Process: Part c8

Follow-up- We covered up opening of connecting

poles with netting to prevent leca and debris from choking them up

Test Phase 4Aims:- To check the sustainability of crop growth

over a prolonged period- To check the suitability of our set up for

growing vegetablesProcedures:- We left the system running for a period of

~50 days (after Phase 3) and made intermediate checks in between

Implementation Process: Part d1

Implementation Process: Part d2

Results (3rd batch of seedlings): - Problem of algae bloom within containment

vessels of system.- Some of the plants fell victim to caterpillars.

One was completely devastated, others were uprooted and thoroughly washed and cleaned before being re-inserted to the system.

- Ants were also found in the system. Eggs were laid on leaves, often resulting in bite holes in leaves.

Implementation Process: Part d3

Dead Plant (Due to Pests)

Implementation Process: Part d4

Analysis- Algae thrive quickly in oxygen, sunlight

and nutrient-rich environments. Favorable conditions exist within containment barrel and tray systems.

- Plants are still vulnerable to pests, which are usually flying and may lay eggs on growing crops. This is because our system is exposed to the outdoor elements.

Implementation Process: Part d5

Follow-up- Water tank was washed to clean off algae

and system was flushed.- More plants added to top layers of system

(Plant added – Kang kong) to reduce algae growth by providing more competition in the layers

Implementation Process: Part d6

Results (Final)- 3rd Batch of Seedlings: In adult stage, can

be harvested soon. Some uprooted due to inability to eliminate infestation by bugs.

- 4th Batch of Seedlings (Kang Kong): growing at fast rate. Some infestation observed and removed.

- 5th Batch of Seedlings (Kang Kong): some germinated.

Implementation Process: Part d7

3rd Batch Now:

Implementation Process: Part d8

4th (Left – Curling Plants) & 5th (Right – Germinating Seeds) Batches