The challenge for the hobbyist is to provide enough light to allow photosynthesis to maintain a thriving population of zooxanthellae in a coral tissue.

The mat is present between apparently healthy coral tissue and freshly exposed coral skeleton.

Drupella cornus is a predator of living coral, grazing on the coral tissue.

The disease exhibits a sharp demarcation between apparently healthy coral tissue and exposed coral skeleton.

The stomach surface secretes digestive enzymes that allow the starfish to absorb nutrients from the liquefied coral tissue.

The initial change (first order effect) is loss of the veneer of living coral tissue.

It causes irregular white patches or blotches on the coral that result from the loss of coral tissue.

Environmental changes like increasing water temperatures can lead to the loss of the symbiotic single-cell algae that live within the coral tissues.

In addition, trawling can kill corals indirectly by wounding coral tissue, leaving the reefs vulnerable to infection.

The lipid-soluble extracts of seaweeds that harmed coral tissues also produced rapid bleaching.