GT Systems Gro-Tank Complete KitGT Systems Lower your media use and improve your yields How it works Plants sit on the GT s sloping tray and nutrient solution is constantly pumped from the tank over the bare roots on the tray above. Whatever the roots don t take up flows down the slope and back into the tank. The solution is continuously oxygenated with an air tube. The roots have unrestricted access to nutrients and oxygen maximising nutrient uptake and growth. NFT doesn t require