If oceans acidify to a great extent, then it will affect many species of aquatic life such as shellfish, oysters etc. They won’t be able to form strong shells or skeletons which may lead to a decline in their population in the long run.
This in turn will lead to a decline in commercial fishing because acidification harms calcifying organisms which form the base of the aquatic food chain.
For more relevant articles refer to the links given below: