This ebb and flow tray measures 4 x 110 x 63cm and is moulded from UV-proof virgin plastic. Gutters run to a deeper drainage point, where you fit a lead through for water supply and return. Those connect straight to 25mm PVC couplings from any hardware shop. A matching aluminium grow table is available.
Used in flood mode, a pump pushes a layer of nutrient solution up into the tray at set times. The water then drains back to the tank, leaving the bed dry between cycles. That keeps roots oxygenated for healthy salad leaves and herbs. Lead throughs are not included.