Most farmed fish we eat is carnivorous eg tuna, salmon. They are usually fed fishmeal or fish oil, originating from wild fish. So eating farmed fish to decrease overfishing is not the solution. The circumstances farmed fish is living in and the damage that’s done to the environment (antibiotics remnants of fish food, excrements of the farmed fish, etc) are extra factors to limit the consumption of these fish.
Some of the farmed vegetarian fish like Tilapia and catfish is more sustainable with respect to fish populations. However, it is wise to check whether the conditions on the fish farm you buy these fish from are environmentally/animal-friendly.
