Lights

plan on doing 12/12 2 hours in the morning under hid lights ..then 8 hours outside for some fresh air and sunshine..then back under the hps for 2 more hours giving 12/12

the question is should i use 400 w or 600 w or will this make a lot of differance since most of it is natural sunlight ?

thanks for your input

If your getting 8 hrs of direct sunlight outdoors then I doubt the difference in watts indoors would make a noticeable difference.
I would save on the light bill and go lower

that's going to be hella work...moving plant 4 times a day?