More plants do not mean more bud. Plant crowding blocking light prevents each plant from reaching its best potential. Also crowding causes stretching because they compete for light. Depending how long you veg for will greatly change your yield. The longer you veg the more you produce exponentially. An extra 2 weeks of veg can double your yield.
If you want to use your 5 gallon pots to their full potential I would recommending you veg for a month at least. with a month long veg and 5 gallon pots I would guess that you could only fit 6-8 plants per light. Remember its 1000 watts per 4x4 grow space and if you are going to grow giant plants then each plant will need at least a foot and a half radius so the leaves dont get crowded. I would expect to yield from that anywhere from 1-4 pounds per 1000 watts depending on the strain grown and other stuff such as CO2 and whatnot.
The yield is mainly set watts per square foot. It has less to do with the number of plants.
Often times less is more
peace
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