Co2 + Lighting come on at same time ?

[freshfish]

is it ok to turn on the Co2 + lighting as same time ?

or do most of you practise turning on the Co2 10-15 minutes before
turning on lighting ? whats the purpose of that?

[Shadow]

I turn on mine 1 hours before light time. I do this so that plant have ready CO2 in the water before the start photosynthesis. But honestly not really sure whether it is really help or not