Fatigue and depression can result from the depletion of B vitamins. Many women with anemia are deficient in three B-complex vitamins: folic acid, pyridoxine (vitamin B6), and vitamin B12. All three are needed for normal growth and maturation of red blood cells. Their deficiency leads to anemia and fatigue.
There is no general rule on what the different ocean fish tend to eat, since they have different feeding habits. However, most of the ocean fish usually eat each other, as well as crustaceans such as shrimp, krill and crabs. Ocean fish also eat kelp, algae, detritus and plankton, as well as cephalopods such as squid and octopus and also echinoderms such as sea urchins. Some ocean fish are scavengers and feed on the carcasses of other marine animals.
Omnivores are the easiest of all fish to feed, as they eat flake foods as well as live foods, and everything in between. For that reason, omnivores are an excellent choice for a community tank. As you can see, it's important to feed your fish the proper diet, as their bodies are designed for certain types of food.