Like other reefs in the world, the US coastal reefs (S. FL and the Keys) are under the pressure of environmental degradation. Coastal pollution, dredging, loss of mangroves, loss of sea grass beds, ocean warming and acidification, fishing pressures, etc. etc. The more developed (i.e. more people and more industry) an area, the more the pressures.
With your aquaculture idea, you should also consider the pressures that aquaculture brings to bear on the environment. High electricity demands, waste water, food for the growing fish....the best foods being based on marine based sources such as crabs, fish, shrimp, krill, etc. that are all wild harvested. Simply put, aquaculture is not the environmental panacea some think, it is simply trading one set of issues for another...while simply allowing some to be ignored.