Hey cesar. Yes, night time prcesses and daytime processes are quite different. I'm just now studying the use of CO2 for my own room, so I don't know a whole lot about it yet. But, what I've read so far, says that CO2 is wasted at night. In my estimation this is because it is during the "day time" or lights-on cycle that the plant executes the processes of photosynthesis. CO2 is used for photosynthesis. When the lights go out, photosynthesis stops, therefore the plant won't be ingesting the CO2 "at night".
If anything above is wrong folks, please don't hesitate to correct me.
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