Reyloads

I am about to buy and air pump, some tubes, and a couple air rod for my planted tank that will be in the future. I know that I also need a co2 system also. I found this great little co2 reactor with a pump (Red Sea CO2 Reactor w/Pump...If anyone wants to see it) But I was wondering how they actually work. Is it like the air pump system but instead of air going through the tubes it is CO2? If so, could I just replace the air pump with the CO2 reactor at night to do the same work?

Thanks a lot!!