I've noticed my ACF has a very peculiar temperament now that I've read more posts from ACF owners.
He's definitely a "wild type" judging by his coloration, but I have yet to see him even try for any fish, let alone catch one. I've seen him munching on moss, rearranging substrate looking for loose bloodworms, chasing around fish flakes with great resolve while ignoring live fish less than half his size.
He's active during the day, mostly when it's bright, but when I switch off the lights to entice my dwarf blue crayfish out for feed he bolts into the nearest cave or into a thicket of moss and refuses to come back out.
He's either very eccentric or mentally retarded.