well...if it would be that simple :) CO2 is best when you grow under strong lights (usually LEDs) and the spectrum of the light is so powerful, that the plant is not able to take more. That's when the CO2 comes in handy. Helps the plant to absorb more light (usually CO2 is added in flowering stage) BUT, there is a BUT... have in mind the CO2 molecular weight vs O2. Usually for a plant to grow healthy, you needs lots of air movement. Fans and extractor fans, so if you have a CO2 bag, then you'd need to adjust and think on the fan and extractors schedule, otherwise it will all be in vain.
Mycelium CO2 that comes in bags works good