I have two 150w HPS lights growing two plants. Could probably get away with three plants.
I would like to get a 400w or 600w HPS and grow four plants, but I may have a heat problem. It's a closet grow and I can't modify it much for ventilation and cooling.
i have a 150 hps n i have two girls that are flowering under it right now.. but i believe that its better for one plant i would have more budz due to the light being not many lumens..
i tried 3 before, it doesnt matter how many plants you have as long as they are in good range of the light.., i wanted to keep a 150hps grow to see yields, and i ended up with 1 plant. diretly under it..
I've done quite a few 250w HPS grows. Overall harvest doesn't seem to change much between number of plants. The more plants I have, the less I get off of each plant. I finally settled on 2-3 plants so I'm guessing 1-2 with a 150hps.
I HATE mylar. PITA to hang and a PITA to keep clean. When my current grow is harvested I'm ripping the stuff out of my flower cabinet and going to flat white paint.