Understanding hydroponics: DWC, NFT and other systems

Choose the crop before the equipment

Start with one crop and a manageable system. Lettuce, herbs and large fruiting vegetables differ in their requirements for space, light and support. Allow access to the reservoir and choose a setup you can clean easily. Decide how you will check the water level and pumps and recognise a failure before it becomes a larger problem.

DWC: deep water culture

DWC stands for Deep Water Culture. Roots extend into a nutrient solution; in an actively aerated setup, air is supplied to support oxygen availability. Water level and root-zone conditions need to suit the design. Adding an air pump to an arbitrary bucket is not a complete growing system: temperature, cleanliness and growing light also matter.

NFT, ebb and flow, and passive systems

• NFT: A thin film of nutrient solution flows through root channels. Reliable delivery is especially important.
• Ebb and flow: The root zone is flooded periodically and then drains again.
• Passive systems: These use a planned reserve or capillary transport. Topping up without following the design can remove an intended air space.

Each approach requires its own operating instructions.

Measurements help, but are not a recipe

EC measures electrical conductivity and helps indicate dissolved salts; it does not identify an individual missing nutrient. pH affects nutrient availability. Use suitable meters and a nutrient formulation intended for the crop, growth stage and system. Include source water and temperature in your assessment. A single target dose for every plant would be misleading.

Build a practical checking routine

Record readings, top-up amounts and plant responses. Keep the reservoir and pipes accessible, inspect roots and remove dead material. Clean between crops according to the system instructions. When a plant struggles, check delivery, oxygen and root condition first. Increasing fertiliser concentration should not be the automatic response.

Frequently asked questions