SAGA CO2 Super Atomizer New Design SG-D201 In-line CO2 atomizer diffuser for freshwater planted aquariums. 12mm (7/16 inch) / 16mm (5/8 inch) OR 16mm (5/8 inch) / 22mm (7/8 inch) Tubing, filters/pumps, and CO2 system are not included. Internal ceramic cylinder produces ultra fine mist for complete dissolving of CO2 gas. Requires a minimum CO2 working pressure of 2.5kg/cm2 (36psi) or greater.