I basically use wall wattage equivalent of 6 cobs/bulbs from top and the area only has 5 plants (6 previously but ran out of space). I then added another 2 cobs (Exactly the same but are blurples) on the side. Top height around 18 to 24 inches once i got the hang of it. If they continue to grow, they will have to accept 12 inch heights soon but i think they will take it well. I have an oscillating fan on them. I just place some blocks on the floor to create my desired height. Then turn all 3500k lights off and only leave the blurple on. I adjust the lights until I'm satisfied with the lighting each plant receives. Just these 2 blurple bulbs is more than enough to illuminate all 5 plants from the side, although the back ones have lesser intensity. They penetrate through lots of bushes which greatly impressed me. I thought blurples are way less intense from what i read.
I have had zero issues with heat and the plants are doing good. Fyi, my temps AND RH is crazy high. A normal day has temps from 28C to 36C and I'm being conservative. RH is 50++ only a few hours mid day when temps can reach 40C sometimes. Mostly its 70ish to 80++. BUT....Ive only begun the side lighting less than 10 days. Can't remember exactly when though. So too early to make any conclusions.
So i got 8 x 60++ watts from wall on only 5-6 plants. Watt meter shows 485w from wall. Pretty similar to your situation with each plant having more than 1 cob. The way i see it, if it works with my rather extreme conditions, should be more than ok with yours. Especially if you're worried about heat.
Another thing to note is that all my bulbs have glass reflectors. I was told they are the same materials as car lights reflectors but different focus. They are perfect for my needs cos they focus the lights better, decrease light loss due to spread (very important for me) and increase intensity significantly.
Its only my first grow so pls take everything with a grain of salt. I'm really curious to see what is
@BigSm0 take on this? He's da MAN!
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