I recently bought 2 threadfin butterfly fish. One made it about 4 days b4 it died, the other made it about 7 days b4 it died. I have several other fish including a yellow tang, foxface, 2 clowns, korean angel, and black sailfin blenny. All of these fish are do fine but what happened to my butterfly. I am mixing pellets w/ garlic and flake food. Was i not feeding the butterflies the right food or does anyone know what might have happened?