Particularly fascinating is the formation of the radial (side) corallites (skeletal cup where the polyps sit within). As the axial (tip) corallites lay down new skeleton, new radial polyps emerge from the sides and develop into the Acro branches we’re all familiar with.

Also, at the 28 second mark of the video (clip 206-2), we see how Acropora heal over broken branches.  Frag away knowing that your corals know how to repair itself as if nothing ever happened.