I feed my bichirs a varied diet ( red worms, night crawlers, smelt, tilapia, crawfish, shrimp, catfish, beef and chicken heart, crickets, mealworms, rosy reds and mollies, frogs, but I've never gave them an oily fish like salmon or mackerel. I was wondering could I feed it to my bichirs not as a common food but maybe once every two or three weeks. Oily fish contain large amount of protein and omega 3. (Possibly make them grow more?)