I have heard from knowledgeable friends that plants do not put out oxygen unless they are photosythesizing, that is, not at night or without light.
True? Anybody know”

It seems that if true, we might want systems designed to keep a grow light ( maybe a full spectrum one) focused on the indoor wall.

Since I hate the idea of using any electric I don’t need to as long as it means mountaintop removal for coal, I would really like the answer to this