The new Optima Professional Aquarium RO DI system truly has it all. Built in pressure gauge to monitor system pressure, Our new percent monitor that warns you when the RO begins to rise in TDS levels, Auto shut off system built in that senses when your storage container is full and turns itself off meaning no more un necessary waste! If your serious about the quality of your water this is the system for you. The Optima Professional also includes all clear filter housings. This system looks as good as it performs! The Professional series is built with a tough aluminum bracket and is backed by our three year waranty. This system does come with a refillable DI cartridge filled with high quality Resintech DI media. This system now includes an all plastic float valve!