My Indoor DWC Hydroponics System

Step 2 The Deep Water Culture Design, Materials and Methods

Please refer to figure 2A for an illustration of the DWC system.

In Deep Water Culture (DWC) systems the plant sits in a mesh basket filled with an inert medium such as clay pellets. The inert medium does not provide the plants with nutrients but only acts as a support to anchor the plant down.

The basket is suspended in a reservoir filled with a solution of nutrients. As the plant grows, the roots will protrude through the holes in the basket down into the nutrient solution where they can be readily absorbed. (Figure 2B)

At the bottom of the reservoir sits an airstone hooked up to an aquarium pump. Air is bubbled through the solution and up to the roots to provide them with oxygen.

Although the leaves must be exposed to light, the walls of the reservoir must be opaque to prevent the nutrient solution from being exposed to light. Not only can roots be damaged by light but light in the reservoir will promote the growth of alge which is harmful to the plant.

The nutrient solution must be changed on a regular basis because the nutrients can be used up and "nutrient toxicity" can occur. Also, the pH of the solution tends to go up as the plants use up the nutrients. It can rise to extreme levels and end up killing the plant.

There are many versions of the DWC system available for retail but they are expensive and aren't DIY. I made mine from materials available at any Canadian Tire and Wal-Mart. Please note that I got the idea for the reservoir system from this build by trebuchet03 entitled Hydroponics - at Home and for Beginners.

I encourage you all to design your own DWC system, using this instructable only as a guide to expand and improve on my design. With that being said I will still provide a complete list of the materials I used below.

Lighting Frame and Supporting Structure:
3/4 inch CPVC pipe
3/4 inch CPVC tees
3/4 inch CPVC 90 degree elbows
1/2 inch CPVC pipe
1/2 inch CPVC tees
1/2 inch CPVC 90 degree elbows
1/2 inch PVC Conduit Boxes
PVC primer
PVC solvent cement

Electrical, Wiring and Lighting:
24 inch fluorescent light fixtures
24 inch fluorescent grow lights
18 gauge wire in black, red and green spools
A grounded plug that can be self-wired
Rocker switch rated for at least 125VAC at 1 amp
Programmable timer*
Wire connectors
Electrical tape
Zip ties
Vinyl shrink tubing
A firm knowledge of Ohm's law, circuit wiring and electrical safety

Aeration:
Aquarium air pump
Aquarium air tubing
Aquarium air bars
Air tubing shut-off valves
Zip Ties

Nutrient Reservoir, Solution and Growth Media:
27 litre storage tote with lid
Can of black spray paint
5 inch mesh baskets*
Expanded Clay Pellets*
General Hydroponics FloraGro concentrated nutrients*
General Hydroponics FloraBloom concentrated nutrients*
General Hydroponics FloraMicro Concentrated Nutrients*
Syringe*

*For those of you that live in the St.John's, Newfoundland area, I recommend dropping by Grow Crazy. I got a lot of my materials there that I would otherwise have to get shipped in from the USA. The guy there is very helpful and there's a great selection of nutrients and equipment for any setup.

Comments

[russvan]

 ive seen that weird blue snorkel tube coming up from the bottom of the bucket in alot of DWC systems, and I cant figure out what it is!! does anyone know?

[PYUS]

semi-transparent tube allows user to view water level inside the bucket ... which must be opaque to block light, which damages roots and stimulates algae.

[russvan]

 makes sense, thanks!

[tj the gnome]

can you include some quantities of each item? i want to get all the parts at once.