The WaterFarm comes in two forms, complete and modular. The complete WaterFarm is designed to be a stand alone system and includes all the items listed below. The modular unit comes without a Drain Level Tube, Elite air pump, Hydroton, or Flora kit, as it is designed to use with a General Hydroponics controller supplying multiple WaterFarm units. This system is sized 1 x 1 This system includes (sold as complete system only):4-gallon reservoir2-gallon growing chamberPumping columnColumn support tubeDrip ring1/2" grommetDrain level tubeElite® 800 air pump9L Hydroton3-part Flora KitThe WaterFarm comes in two forms, complete and modular. The complete WaterFarm is designed to be a stand alone system and includes all the items listed below. The modular unit comes without a Drain Level Tube, Elite air pump, Hydroton, or Flora kit, as it is designed to use with a General Hydroponics controller supplying multiple WaterFarm units. This system is sized 1 x 1 This system includes (sold as complete system only):4-gallon reservoir2-gallon growing chamberPumping columnColumn support tubeDrip ring1/2" grommetDrain level tubeElite® 800 air pump9L Hydroton3-part Flora KitThe WaterFarm comes in two forms, complete and modular. The complete WaterFarm is designed to be a stand alone system and includes all the items listed below. The modular unit comes without a Drain Level Tube, Elite air pump, Hydroton, or Flora kit, as it is designed to use with a General Hydroponics controller supplying multiple WaterFarm units. This system is sized 1 x 1 This system includes (sold as complete system only):4-gallon reservoir2-gallon growing chamberPumping columnColumn support tubeDrip ring1/2" grommetDrain level tubeElite® 800 air pump9L Hydroton3-part Flora Kit