@popcornsutton, Depending on the plant 8-12 ounces should be doable. If really good genetics maybe even a pound. If you look back at my Durban Poison grow. That was two 3x3's I had next to each other. One had the 240 ac infinity light and the other had the 400-watt bestva but the one with the 240w yielded better because they were two separate seeds. I did 30-gallon pots for those grows and think that is plenty. Even though my roots stretched to the bottom of these 65 gallon pots. I didn't see a much bigger yield than from my 50-gallon pots. and i dont even think 50 gallons would fit in a 3x3 with enough space for a fan. 20 gallon may even be the better sweet spot for giant pots in a 3x3. I think you would yield better from 4 smaller plants though in 10 gallons.
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