Hi Malihuana! I thing it's something about white led substrate, but you have some cyan leds, not very powerfull but work on this region
Example: Lumileds LXML-PE01-0070
Did you want to make a flat spectrum?
if you look to a daylight spectrum - it is much more even than e.g. white ~ 6500K led spec.
No gap around 500nm. In natural sun light the region around 500nm belongs to the most intensive wavelenght inside the spectral power distribution and some carotenoids are very activ inside this range. --- so yes - i want to try a more linear (flat ?) distribution and that`s why i added 400nm, 435nm, 490nm to different warm white leds.