Originally Posted by cheesehead
I think that 80 XML's will be overkill. You'll be at 400 - 500 PAR. There are some spreadsheets here for figuring out how many LED's and how much light, Hoppy's set one up.
I'm looking to do a similar build but am looking at ~20 XML's with a similar mix - about 10-15 violet, a few green, and about five red for full spectrum. About 100 PAR max with the lights 36 inches off the substrate, with the ability to turn the light down.
thats why i needed help but only 60 (still prolly to much) xm-ls as daylight midday
i heard that greens and blue do nothing but when i looked at par charts chlorophyll a takes 450ish nm and 660 ish while chlor b takes 430ish and 640ish with greens and yellows rather nonexistent this confused me badly thats why i wanted help
i hope this helps you as well