It's my understanding that it's the excessive carbohydrates fed to carnivorous fish, not the protein, that causes fatty livers. However Dr. Paul Brown of Purdue that does extensive research on feeds has told me that unlike humans, fish can be functional diabetics (fatty livers) and survive just fine.
On another note also from my understanding the premature deaths of pellet fed fish is not totally understood. As in LMB something seema to be missing in their pellet diet but no one seems to know what for sure.
I agree with one of the posters on this. If you are not feeding fish that need the extra protein why spend the extra money for it you don't need. Bluegills, talapia, and catfish can get by with less protein.
