LiquaGen &ndash; 7 Stage &ndash; 0 PPM Aquarium Reef/Deionization Reverse Osmosis Water Filter System (RO/DI) | Heavy Duty w/ 100 GPD Capacity This product is great for aquariums, laboratory testing, and other applications for pure water. Pre- Assembled system for easy installation. Guaranteed 0 ppm water. Installation takes approximately 5 minutes! Manual Flush Valve makes this system superior to any other RO/DI system in the market by increasing the life of the unit, reducing possible leaks, and saves you valuable time when flushing the system every few months. High Rejection Reverse Osmosis (RO) Membrane. Film by GE USA 2 year manufacturer warranty; Lifetime customer support