Depends on the tank what you keep.

First white led

6500K could supply the energy to plant and coral

11000K is the strongest sunlight,could promote the growth for the coral,suitable for the saltwater tank

now we talked about blue led

450-470nm could make the sense like deep blue, suitable for deep water coral,

420nm uv, some coral like yuma and so on have fluorescence color, UV could promote this wave and enhance this effect. Now the popular led aquarium bar is very suitable for the slim tank,middle size.

LED could use these few color together in one bar, but other no.