Simple Beginner Systems (Kratky, DWC)
The Kratky method is the simplest: a sealed container of nutrient solution with a net pot in the lid, no pump, topped up occasionally - ideal for lettuce and herbs. Deep water culture (DWC) is similar but adds an air pump and air stone to oxygenate the solution, which supports larger and faster-growing plants. Both are cheap to build from a tote and a few parts and are a good first step before more complex flowing systems.