PAX BELLUM N18 This innovative algae reactor provides reef keepers with the ultimate tool to export nutrients and maintain nitrate and phosphate at levels required for vigorous SPS coral growth. The ARID is a work of art and it’s patented design is based on more than a decade of research and development. As an option, you can order a Ca Reactor Feed/Injection Assembly to send excess CO2 from your calcium reactor right into the ARID, which further benefits the growth of macro algae. Light Tube Assembly should be replaced after 10-12 months. Learn more behind the chemistry of the Pax Bellum ARID, plus more here. Specifications: Recommended System Size: 40-120 gallons Recommended Flow Rate: 150-200 gph Recommended Pump: Maxijet 900 (pump not included) Total Height: 16.4″; Total Footprint: 6.5″ 1/4″ FNPT inlet/outlet ports