Yes MH or multi vapor is the only way to go for veg. Blue light builds chloroplasts while yellow light converts them into sugar and starches which the plants use as food. The hortilux ace is the best MH I know of. All depends on the spectrum.

Here is what the sun has...
ci = 3.14814814814814 (refer to GorillaGrow.org(anic) Home of Organic Chemistry Homepage to see more)
100 / ci = 31.764705882352941176470588235296 or A
100 â?? A = 68.23529411764705882352941176471 or B (%yellow)
B / ci = 21.674740484429065743944636678203 or C (%blue)
B + C = 89.910034602076124567474048442913 or D
100 â?? D = 10.08996539792387543252595155709 or E (%red)
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Three primary colors.
Spectrum 360-720
This gives three groups of colors with a 120 nanometer gap each group
The mid point would be half way through giving the first color blue at 420nm.
We would simply add 120nm to get the mid points of yellow and red.
420(blue) 540(yellow) 660(red)
Green is 425 nanometers
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.6823529411764705882352941176471 x 540 = 368.47058823529411764705882352938

.21674740484429065743944636678203 x 420 = 91.03391003460207612456747404844

.1008996539792387543252595155709 x 660 = 66.5937716262975778546712802762

526.09826989619377162629757785394 is the total. 525 nanometers is green.