which LEDs are you using?
what colors are you missing?
Its all about knowing what wavelengths are going to bring out which colors. People using a cool white and royal blue combo will loose reds, oranges, pinks but their greens will explode.
check out the thread on
full spectrum and OCW (Ocean coral white) LEDs.
If you are looking for color, thats the best place to check. Makes a huge difference.
FYI whoever is telling you its a technology thing is blowing smoke up your @$$. Light is light, it doesnt matter if its T5, MH, or LEDs. Its about the wavelengths. match the wavelength and locus of a MH with LEDs, its going to be the same light and will have the same effect.
But as the thread linked above will show you, MH are cookie cutter and you are stuck with their attributes. With a bit of testing (as the guys in that thread have done) you can take the right LEDs and the right ratios and produce some incredible colors in corals (AND FISH!)