SAGA CO2 Super Diffuser New System 16/22mm SG-D101-16-S In-line CO2 atomizer diffuser for freshwater planted aquariums. 16/22mm fittings included. 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.