Coral growth and lighting coverage

[clownfish_forever]

Hi brothers,

I have a curious question on coral growth with regards to the lighting coverage they receive.

1) For SPS, as the colonies grow some part of the colonies will be blocked from the light from the new growth. Does that imply that those shaded area will die off or simply the area receiving the light will sustain the life for the entire colonies? Means it is fine that some areas are shaded?

Then extending this question to LPS and zoas.

2) For LPS, some corals with mulitple heads like hammers, frogspawn, does it matter if 1 head is shaded from light? Does that mean that head will die off?

3) Similiarly for zoas, sometimes we bought a big ball of zoas but due to placement, some polys may not get the lights, does that mean those polyps will die off too?

Thanks!