Introduction: Floating Veggie Raft for Fish Ponds

About: I design and sell hydroponic systems

Use a floating veggie raft to help filter your fish pond water and grow vegtables and fish together.

Equipment needed

Materials needed
Polystyrene sheet (30 to 40mm thick). I used a piece from packaging that was to be thrown away. (1m x 0.8m) R50.00 = $5.00
Plastic garden netting 2m x 1m (I used 4mm as the pond has small fish, 12mm should also be ok) R50.00 = $5.00
5cm slatted pots x 16  R16.00 = $1.60
Coir fibre (coconut hair) 50 grams  R5.00 = $0.50
Vegtable seedlings  x 16 (Lettuce in this case) R16.00 = $1.60
Cable-ties (1 pack of 100 small cable-ties) R15.00 = $1.50 

Tools needed
50mm hole saw
40mm hole saw
Electric drill
8mm Drill bit

Total cost for materials without tools in South African Rand R152.00, U.S. Dollers $15.20
Time - Approximately 6 hours

Step 1: Measure Length and Width of Polystyrene (for the Plastic Garden Netting)

I used a discarded piece of polystyrene packaging for my floating portion of the veggie raft

Step 2: Measure and Cut Garden Netting

1 x Base (1m x 0.8m)
2 x Sides (1m x 0.3m)
2 x Sides (0.8m x 0.3m)

Used scissors to cut the garden netting to size

Step 3: Join Sides of Netting

Join the sides and the base of the netting with cable ties.
The net is to stop fish from feeding on the roots of the vegtables.

Step 4: Cut Holes in Polystyrene

Measure and mark the distances between the holes to be cut.
Pre drill each hole with the 8mm drill bit (acts as a guide from both sides of the polystyrene sheet).
Cut holes in the polystyrene sheet with a 50mm hole saw first. Cut about 20mm deep.
Use the 40mm hole saw from the other side to complete the hole.
This leaves a step for the 5cm pot to rest on.
Drill 8mm holes on the edges (To attach veggie raft to the netting).

Update: one can also use an offcut piece of car exhaust pipe, heat with a blow torch, proceed to make the holes for the net pots

Step 5: Attach Veggie Raft to Netting

Attach the raft to the netting, netting on the outside of the raft. (To stop fish getting into the net)

Step 6: Plant Seedlings Into 5cm Pots

Remove seedlings from seedling tray, rinse off the roots. Wrap the coir around the roots and fit into the 5cm slatted pots

Step 7: Float the Raft

Float the raft and insert the 5cm pots with seedling into the holes.
Make sure that the bottom of the 5cm pots are just touching the water

Step 8: Wait

You are done, wait for your veggies to grow on the fish waste and help filter nitrates and nitrites from your pond.

If you do not have fish that feed off plant roots, there is no need for the net.

Harvest and enjoy


Graham L

Step 9:

Week 1

Step 10:

Week 2

Step 11:

Week 3

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