For years people have scorned the vegetarian diet, yet as our food supply becomes more and more tainted, eating vegetables may be an easier food source to be sure of with regards to not being as tainted as fish, meat or dairy.
Most fish nowadays is farm raised and that is essentially the same as factory farming, except in the ocean. This means it contaminates the ocean with antibiotic residues fed to the farmed fish as well as toxic chemicals used to prevent algae overgrowth. Additionally, weak and diseased fish spread their disease, that is inevitable in factory farming, to wild fish stocks. Wild salmon stocks are crashing as is the fishing industry worldwide.
Recent government funded studies have found levels of PCBs, dioxins, mercury and other toxic chemicals to be higher in farm-raised fish than wild fish. Unfortunately, of all the fish tested, both farmed and wild, these toxins were found in all of them at unacceptable levels. Fish farms even feed synthetic pigments to their fish to make their flesh look more appetizing.
My advice would be to grow your own veggies and buy organic as much as possible. If you grow your own, you might want to think first before using fish emulsion as a fertilizer.