I don't agree. For the last 30 years I've been making my own fish food. Canned spinach, whole eggs, table shrimp, liver, 1/2 raw carrot. Throw it in a blender then heat in nonstick skillet until jelled. Two months ago I bought a sail fin tang and tried every food fresh or frozen, flake, anything I could think of and he refused them all. After a week of that I whipped up just some spinach and egg and after a few tastes he began to eat. Now he eats all foods but the egg and spinach got him started. I've raised freshwater fish from eggs for their entire life on homemade food and have even fed it to anemonies along with most types of marine fish. But like with all else variety is still important.