5 plants or 9?? for besy yield

Hi guys
I have been growing for some time and been using different seeds fromm various banks.I have been using 2x 600w diamond hoods in an xl bud box filters and prim air controlng the air.So iam happy with the grow room.I have a very experiened friend who generally hits optimum s of a gramm per watt.Unfortunatley he can only give advice over the internet as he lives some way frm me.I have been only reaching about half of his yield but he recently bought me some cuttings down from a mother he has had for a long time of a pure power plant he assures me it has massive yields.My reall question is howmany plants should i have under one hood? My man assures me i would only need 5 or 6 but i have also read of 9 .also would you need to veg them for a longer time if you only had 5.Any advice welcome

I put 7 to 9 plants per hood. I also run 600 watters.

I just give the plants around the edge a quarter turn everyday and it works great.

cool does it matter if ligh is going through the space cause i dont think 5 will fill the area iam told not really little bit confused