Barramundi Fish... If the Barramundi fish were a human, he would be a tree-hugging, salad-loving vegetarian. The Barramundi, hailing from the coast of Australia, eschews his fellow fish, dining on plankton instead. That means he doesn't load up on mercury-packed smaller fish and has extremely low levels of the toxin, which is especially important for pregnant women. Free of mercury, but full of heart- and brain-healthy omega-3s.