I those lights have veg & bloom switches I wouldn't even do 2 plants. Just being honest. I have 2 "600w" led's too.
what about 2 pp plants in that size . i was thinking of actually bumping down to 3 plants 2 pp and 1 autoI wouldn't. Well let's say I shouldn't have... but I did 3 plants in the same size tent. 2 auto's 1 fem photoperiod. Bad idea. Had to boot one out of the tent because of space. The PP plant may be sacrificed if the auto's don't hurry up.