Fish oil is an important part of Paul B’s fish feeding regimenHobby pioneer Paul “Paul B” Baldassano has some strong opinions on what types of foods are best for fish, formed over his many decades of involvement in the marine aquarium hobby. Somewhere near the top of his list is fish (or krill) oil. He explains exactly why in the following excerpt from the third chapter of his book The Avant-Garde Marine Aquarist: A 60-Year History of Fishkeeping:From Chapter 3: Keeping Fish Healthy Oil, in my opinion, is one of the most important things you can feed to fish. No, not Oil of Olay or olive oil, but fish or krill oil. I take it myself every day, but not too much, as I don’t want to resemble my old flounder-faced girlfriend. In the sea, fish get a large percentage of their diet from pure fish oil.