Basic Deep Water Culture (DWC)–style hydroponic setup, a “passive hydro box”.

basic Deep Water Culture (DWC)–style hydroponic setup,  a “passive hydro box”.

20251109 

this black container with holes sitting inside a white tub is a basic Deep Water Culture (DWC)–style hydroponic setup, or what’s sometimes called a “passive hydro box”. It’s simple, effective, and well suited for testing bitter gourd and leafy vegetables.

Here’s what’s happening (and how to optimise it):


⚙️ How Your Setup Works

  • White tub: acts as the water reservoir (stores nutrient solution).
  • Black container with holes: acts as the net pot tray, holding your growing medium (coco peat, perlite, or clay balls) and plants.
  • Roots grow through the holes and hang into the water/nutrient below.

How to Make It Work Better

1️⃣ Water level:
Keep nutrient water level about 1–2 cm below the base of the black tray — so the roots get air and don’t drown.

2️⃣ Air access:
If possible, add an air stone or small aquarium pump to oxygenate the water — especially for bitter gourd, which has hungry roots.

3️⃣ Sunlight:
Because your area gets strong light, consider shading the white tubs slightly (to prevent algae) but let the plants themselves get sun.

4️⃣ Nutrients:
Start weak — EC around 1.2 – 1.4, then increase to ~2.0 as vines mature. Bitter gourd is a heavy feeder once it starts flowering.

5️⃣ Support:
You can tie strings or thin bamboo canes to the back wall or your existing trellis system — bitter gourd vines will climb naturally once the tendrils appear.


🌱 Good Plants for This Same Type of Hydro Box

In addition to bitter gourd, this size (≈30 × 30 × 20 cm) setup is also perfect for:

  • Lettuce / Butterhead / Romaine
  • Kang Kong (Water Spinach)
  • Coriander (short harvest)
  • Mint
  • Chye Sim (baby stage)
  • Basil

They grow well with the same tray-and-tub combination.


Would you like me to make you a labelled diagram (top + side view) showing how to:

  • place seedlings in this tray,
  • water level position,
  • air stone location (if added),
  • and how to connect to your rainwater / solar spray system?