Do amino acids and trace minerals have much to do with fish food or does it not matter?
What about palatability? What is used to help minimize "pick and spit"?
You said that there is no difference in digestion between LMB, BG and carnivorous catfish. Are there differences in nutritional requirements for each of those 3 species?
Amino acids determine protein digestibility so yes they are crucial. Minerals may not be needed because of what they eat naturally but is a nice hedge to insure they are getting all they need.
Fish meal, Fish Oil and I have heard Hydrolyzed Fish along with salt are all good. Shrimp meal is better than all listed above but the protein digestibility is so poor I wouldn't recommend it.
Once the pellet goes down the gullet a carnivore is a carnivore is a carnivore.
