Flow Phase (Flood): A submersible pump in the reservoir, often connected to a timer, pushes nutrient solution up into the grow tray where plants are housed in inert media (like clay pebbles or coco coir). Overflow Management: The tray features an overspill fitting (valve). As the water level rises to the top of this fitting, it prevents the tray from overflowing while helping to ensure all plants are properly submerged without flooding the floor. Ebb Phase (Drain): Once the timer turns the pump off, the nutrient solution drains back down, usually through the same pump or a separate drain fitting in the tray, returning to the reservoir. System Benefits: This cycle ensures plants get water, nutrients, and essential oxygen. The draining action pulls fresh air into the growing medium, allowing roots to breathe, which prevents them from staying waterlogged.
