light period

Hi mate, I do this and always have done for the first couple of weeks of my indoor grows. I always compare my starts to other grower and even though my CO2 level are higher than ambient, I notice the great progress mine has over some others. No need to change the light height as its not the intensity you are changing its the rest period you give the plants. They suck in CO2 during the day and expel O2 at night. Having high co2 levels will take your grow to the next level when using the 24hr -18 hr technique. She will drink more water when exposed to more CO2 so keep that in mind. I hope this helps, good luck and happy growing