The Under Current® Systems are ideal for large-scale commercial growers. With the patented Sub-Current Culture® circulation method, growers can now improve operational efficiencies and overall yields. Sub-Current Culture® (SCC) technology utilizes negative water pressure to recirculate highly oxygenated nutrient solution through the plants root zone. This continuous fluid motion supercharges the nutrients with dissolved oxygen, creating hyper-aerobic conditions perfect for explosive plant growth. High levels of aeration and constant circulation optimize plants nutrient uptake capacity. This action conserves nutrients, water and necessitates less frequent nutrient change-outs. 40 inch plant centers with recommended growth time of 4-6 weeks. The Under Current® Systems Includes: 13 gallon Blackout Series growth modules, 3 in manifold & joints, 3 in UC Spin-Tight Bulkheads, growth module lids, one 8 in net pot per growth module, Danner Mag-Drive Return Pump, Premium Linear Air Pump(s), 9 in air diffuser disc, Aqua-Pore Air Diffusers, air distribution manifold, air hose, in-line filter, adjustable float valve with reservoir adapter kit, drain valve, chiller adapter, garden hose drain adapter and Cultured Solutions VEG A/B. 16 site has a 18 ft x 20 ft grow area, 24 site has a 18 ft x 28 ft grow area and 32 site has a 18 ft x 34 ft grow area. These items are drop ship only.