Ebb-N-Grow Controller Bucket The Ebb & Gro Controller is the missing link for hydroponics gardeners making their own flood and drain system. This 3.5 gallon unit has pre-installed float switches and comes with a cover, necessary fittings and two 315 gallon-per-hour submersible pumps to facilitate the fill and drain cycles. The attached controller regulates the cycles and can manage six to 48 separate plant sites, has easy-to-set 15-minute interval pull tabs and is warranted against defects for a three-year period. The complete Ebb & Gro Controller also includes instructions and extensive support materials.