A new study suggests farmed fish could be key to feeding a growing global population. Fish are an efficient source of protein and already over half the fish we now eat are farmed. However, this phenomenal growth in the production of salmon and other popular seafood has had a detrimental effect on their wild cousins. Wild salmon numbers have fallen and conservationists blame the fish farms for the spread of disease, sea lice and the pollution of habitats. Most farmed fish also require a diet which includes smaller wild fish in order to help them create Omega-3 which has well documented health benefits for us all. This too has an impact on the wild fish stocks with many key species now under pressure. Tom Heap investigates the dramatic and novel approaches which the industry may need to adopt in order to keep up with our appetite for fish suppers and it seems the best solution for the health of our oceans might be to take the fish we eat and the food we need to feed them out of the sea altogether. Producer: Helen Lennard.