1kw bulbs are cheaper per watt, are equidistant on the floor plan, and yield more than 600w. on a 12 plant/13 light layout, and the perimeter plants get 3 kw, while the inside plants get 4 kw. if you use (5) 600w in the middle, then all the plants get 2.6-2.8 kw. is there a good reason you'd want to evenly light the plants, aside from even growth?
I put an extra row of plants to use the end lights better. the 10 plant layout only uses 45* of the two corner bulbs. also canadian medmar laws allow 6 plants per patient (my personal concern).
X=1kw
x=600w
O=plant
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