Yes, larger fish tend to be more intelligent, but mormyrids have very large brains (most of the energy received goes to their brain) and elephant noses are intelligent enough to play with a ping pong ball. http://www.monsterfishkeepers.com/forums/showthread.php?568535-Monster-Mormyrids! Here is a thread I made about large mormyrids.Aweshade, Jesus, 3 feet? Never mind, lol! I don't think a three foot fish would do well in a 75 gallon. Are the Elephant Noses prone to doing tricks like the Kannume? By tricks I mean pushing a ping pong ball around the tank, going through hoops, etc? I've seen videos of them being hand-fed though, which is pretty awesome. I love their cute little trunks!