space yield light question

ok i am growing hydro on a 3x3 ebb and flood system i am 13 plants on it it is starting to look like a forest have been in flower since feb 18 ...i was wondering if i where to have 13 plants or 5 plants would it be the same yield i have a 600 watt hps light i heard that it only maters on the watts not the number of plants is this tru

ne one come on i kno people can see this

i'm thinkin you'll get way more out of the 13 then just 5. but WTF do i know i'v been groing for 3weeks haha

well now you know people can see it thou

lol good looking duke thats what i thought to but some people

how tall are you going to grow that plants

the average hieght was about 18 inches

well If you have the room I think that power would do better for less plants if you were going to go small i would say do the 13