Not a lot of details here other than the "reef stars" which provide a substrate for new coral growth. But what led to the coral death in the first place? Probably warmer water - not sure how this helps with that unless they're attaching species that can do well in warmer water (such as corals from the red sea, for example). There could have been other issues that led to coral death in that area such as an overabundance of nitrogen and phosphates from fertilizer runoff - unless that's addressed it's going to keep happening.