Will a larger Gulper catfish eat a Smaller one?

[thebiggerthebetter]

AFAIK, gulpers do not eat gulpers. One gulper needs not to be of smaller size for another gulper to swallow it. They may mouth each other apparently accidentally but then do spit out. IDK of exceptions to this rule. They may or may not exist.

I've just lost two 9"-10"ers (3-4 years old) for no reason I can fathom but just rather groundless guesses. Got only one left.