The Red Flex Reef sumps feature a modern red and white acrylic design designed specifically for saltwater systems. Water flows through the two overflow ports, into a proprietary bubble diffuser, and through the 4 inch 200-micron filter socks. Each sump includes an overflow panel where the water can escape into the sump if your socks overflow. The Red Flex Reef Sump is equipped with a dosing, probe and wire holders, easily maintained by the built-in fastener. With an adjustable water level exiting the refugium chamber via the adjustable flow gate, the water level can be adjusted from 6 to 9 inches, depending on your specific needs. Standard features include flexible hoses, 4-inch Micron bags, and the foam block sponge.