OK, if I decide to go for example for the above ( 4 V29s @ 1.4A), which will add up to 200 W per bar. How hot are we talking? What cooling do I have to get for them? What temperature could they reach, and at what temperature should I run them? How many fans would I need, how powerful? Or could I run passive cooling for this kind of setup? The heatsink(s) - are there available kind of what i showed in the picture above or will I have to change the desing concept... I want them to be as harmless as possible to the plants at, let's say a foot of distance (comments on the distance? ).
One more thing! You mention color temperature of 4000K. I am going to use these light only for flowering do you think this is the best CT. What is 2700-3000-3500K range about? Isn't it better for flowering? Or a mix?
Thank you all again for the "lessons"

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