My best is 21 zips from a 350w output lamp over 10sq/ft using 14 Vero29g5 at 700ma, 25w each.
Currently running 8 CLU058-1825s 50w each in the same space, about halfway through the grow now, it's looking nice and I'm probably going to get somewhat better yield and g/ft, hesitate to say better GPW but lamp efficiency went from 42% to almost 60% so it's possible. I will need to hit 24 zips (and 67 g/sqft) to hit the same GPW. The space is slammed with light. I would have several others running but I have a pythium issue I've been trying to work out.
It's all hydro so not comparable with a soil grow, but still...
Day 26 of 12/12, 3500K 80CRI on the left, 3000K 70CRI on the right:
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