Well thats light effiency for growth.
If light makes coral change color is another thing.
My most beautiful coral is a Montipora digitata but thats only under Par about 500. In that light it is clear light red to pink. Under 200 par it grows much faster but is pale orangered. In strong light the corals forms light protecting proteins and many times they have what we see as the best color. But it takes a lot of energy to do that and the coral grows slower. These substances grow slow and thats why we have to go slow when we increase the light.
If light makes coral change color is another thing.
My most beautiful coral is a Montipora digitata but thats only under Par about 500. In that light it is clear light red to pink. Under 200 par it grows much faster but is pale orangered. In strong light the corals forms light protecting proteins and many times they have what we see as the best color. But it takes a lot of energy to do that and the coral grows slower. These substances grow slow and thats why we have to go slow when we increase the light.