I just got the Eheim Aquaball 1212 from Bigalsonline and I don't understand how the integrated diffuser works. See second pic.. There is an attachment that goes on the output nozzle that has a hose and adjustable knob on it but I dont' know how CO2 can connect to that thing. Once I get my Rhinox 2000 I plan to run CO2 through that and have the Eheim collect the uprising bubbles and pump them through out the tank. In the meantime can I hook up my co2 line to the Eheim and let it diffuse CO2?