i making a grow box 5'high 4' wide and 4'deep useing mylar as a reflector for the sides. but im not sure if i should use a 250 watt hps or a 400hps i got great ventilation but im wondering if the 400hps is going to be over kill? and how much yeild could i expect from a grow box this size? and with which light?
your gonna need at least a 600w HPS if your gonna be using the entire 4' x 4' area... or 2 400w lights.... you need at least 35w/ sq. ft., better yet 50w/ sq. ft.
i could always just hack off a foot from each side and the top cause i cannot afford 600hps or 2 400hps