Waves are folds of water cause by the gravitational pull of the moon.
When waves occur, it mixes the water and makes it to where there's less algae and gunk in the water, making it more inhabitable for sea life.
Sponges are similar to other animals in that they are multicellular, heterotrophic, lack cell walls and produce sperm cells. Unlike other animals, they lack true tissues and organs, and have no body symmetry.
The shapes of their bodies are adapted for maximal efficiency of water
flow through the central cavity, where it deposits nutrients, and leaves
through a hole called the osculum. Many sponges have internal skeletons of spongin and/or spicules of calcium carbonate or silicon dioxide. All sponges are sessile
aquatic animals. Although there are freshwater species, the great
majority are marine (salt water) species, ranging from tidal zones to
depths exceeding 8,800 m (5.5 mi).
The answer is Climate change. It will take decades for the
coral reef to recover from the catastrophic climatic changes including El Nino
in 1997-98. Climate Change is the main and undeniable threats to the loss of
the corals. It has negative effects on coral populations in some ways. This
includes the Color Bleaching, Coral Disease, and Ocean Acidification.