Less than 300 works for me. The room itself is 8x8 w\8 ft. ceilings, but to my understanding, I wont have enough lighting for the entire room. Which is why I was leaning towards 2-20 gallon tubs w\ 4 sites on each. That would leave 5 gallons for each plant, plus cut down on the lighting and space I would need. I wanted to frame in a 4x8 section so I could have enough lighting for the space.