Salmon farm raised or wild

Well Salmon is a very good fish to eat but between farm raised and wild is very different, first you have farm raised salmon that has more PCB than the wild salmon,most of the salmon on the market is farm raised which means the salmon are in cages or nets,you see all the crowded conditions cause alot of contamination,this is what causes high levels ofPCB,i myself will only eat wild salmon most of the stores sell fresh farm raise salmon,most of the wild salmon in the stores is frozen which is i believe is better because they catch the salmon and it is frozen right there.That so called fresh farm raise salmon really who knows how long it has been out.