What conclusion can you make about the relationship between the ph and the biodiversity of the coral reef ecosystem in the simulation?

Lower pH value (more acidic) affects the amount of calcium carbonate in the water of coral reefs. This has consequences on the coral skeletons, because they are made of calcium carbonate. It can be a huge problem (since the coral reefs are resource of food and tourism), it is going to be  harder to them  to calcify or they could even dissolve.

So, decreased pH could decrease biodiversity of the coral reefs if  'ocean acidification' continues due to absorption of atmospheric carbon dioxide.

not only is it colder, it also becomes darker, less salty, and more dense.