One of the best features of an ebb & flow system is the versatility to add and remove plants easily. The 15 individual planters included with this system hold grow rocks for each plant. The large 7.5 gallon reservoir features a handy drain/nutrient level gauge on the nutrient level. A powerful yet quiet pump sits in the reservoir and fills the upper growing tray when activated. The MegaGarden is suitable for growing a wide variety of plants, including flowers, herbs, and tomatoes.