well, I feed every night, he eats every night, so does the snowflake eel. Neither have shown any hostility towards the other fish in the tank. There is even a tomato clown that is continually swimming around the Lion. He apparently feels quite safe.
I have been told not to feed daily, but frankly, if it keeps the peace, I will do it.
I mix my own food made from scallops, shrimp, fish, squid and garlic oil. He eats anywhere from 3-5 hunks of a little bigger than 1 inch pieces each evening. It has been my experience with both the Lion and the Eel that they will not assume a hunting posture unless I havent fed them.
Incidently, he is target fed so that I know he has eaten. He has added at least an inch, if not two, in length in the last couple of months.