information needed on lights room ect

hi people how much light would you say is needed per plant i hav 16 plants at diffrent ages growing under a 600 watt super nova plants are growin but some more than other what would you advise do they need more light or not and what yeild would you exspect to come from this at a rough estimate they are all close together does this matter and also how high sholud they roughly b after a month of growin they are indica plants and advice would b reli apresiated thanks

also wondering why the leafes are curling around each other on some plants any help wud b greatful on any of the questions