The WaterFarm 8-Pack Controller Kit comes complete with eight WaterFarms, a Standard Controller, three-part Flora nutrient kit, a dual-diaphragm air pump and all the necessary tubing. This versatile kit can be arranged to fit most spaces, packed close together for small spaces or spread out to accommodate larger plants. It's an excellent option for any grower. The controller module consists of a 13-gallon master reservoir that sits on top of a 8-gallon controller reservoir, which is then connected to the first WaterFarm in the chain. Controller has a float valve that draws nutrient from above any time its level (and that of all the WaterFarms) drops below a preset level. This system allows users to maintain the nutrient level in all connected units for days or even weeks.