No cooler fish than BGK
We've had a BGK for about a year and a half, and at first had him our 36 gallon community tank (we took a chance in adding him, when we already had an African brown knife). He was only about four inches long when we got him.
Now we have transferred all fish to the new 55 gallon, added plants and driftwood, and more tankmates. He (she?) is by far the coolest (and baddest) fish in the tank.
We feed him by hand. He is so tame that he seems to enjoy being petted. He loves tubifex, and will usually take two cubes just by himself, even with competition from the other fish. And he knows when feeding time is.
There have never been any compatibility issues with the African knife, although the African has only reached six inches. The BGK now dwarfs him at about nine inches. Pretty soon, we're gonna have to create a bigger cave for him...
For anyone interested in getting one of these fascinating creatures, I recommend doing your homework. Allow plenty of space, including hiding places, and a 'den' of its own. I have seen other posts that address small tankmates. We try to stay away from purchasing small fish, with the BGK in mind. They (small fish) seem to disappear mysteriously, although we have not witnessed any actual 'crimes in progress'. Shrimp, anyone? These'll provide the challenge the BGK seems to need, and distract it (temporarily) from any other unintended prey. Until the shrimp are gone...
I hope we'll be able to keep this guy around for a long time.