This is the kind of hydroponics that most people think about when thinking about hydroponics. The hydroponic system has a constant flow of nutrient solution so no timers are required for submersible pumps. The nutritional solution is pumped into a growing tray (usually a tube) and flows over the roots of the plant and then flows back into the reservoir.
Usually, no planting medium other than air is used, which saves the cost of replacing the growing media after each harvest. Typically, these plants are carried in small plastic baskets with roots, which depend on nutrient solution.
