i too dont understand these red/blue only grow lights. i understand that's where cholorphyl PEAKS production, but if you look at the data there is activity going on at any point in the spectrum- maybe you can say green doesnt do any good, but whos to say it doesnt have some benefit that we just dont know about yet. remember, your plants have adjusted to use sunlight for millions of years. youre not going to change their habits in a cycle or two.
i think, ideally, you give your plants the closest thing to sunlight you can get. and thats white light. the pictures prove it too! if you look at these red/blue grows, theyre weak shit! just the pics in this thread alone look a lot better, a lot more like hps grows!
i am planning on making my own led lights. im shooting for 500w output for about $850 retail price. my color choices have concentrated about 70% as 'warm' white, with about 20% red led's to spike the flowering, a couple blue led's to boost the vegging, and a couple small UV led's to promote resin production. best i can figure, this should be an ideal combination. time will tell though!
and some do not 
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