I think my upside down catfish is eating his fish tank friends?

[Lonna Lynn]

I have a 5 gallon tank with live plants in it and one log. For a while I just had my upside down catfish in there and since the tank is mainly for my son I bought other fish because the catfish hangs out in the log all day and comes out at night. I bought one very tiny angel fish and 3 neon fish. They were all healthy when I bought them. About 2 weeks ago I noticed that one of the neon's was dead, one was alive and one was M.I.A. I thought it was weird and I looked around and couldn't find the other fish. So now I just had the one neon and the angel fish. Well this morning I could night find the angel fish to save my life. Its black and the tank is pretty bright so I would of noticed him floating or at the bottom. The catfish isn't more than 3.5 inches long and I thought they weren't carnivores. Also it is pretty impossible for the fish to jump out of the tank because there is not one opening and I think I would have noticed a fish on the dresser or floor.
So my angel fish ate itself?

[pinkempyreal]

It is possible that the fish died, and then got eaten by the catfish. A 5 gallon fish tank is hardly enough for one fish..