The guys that keep FH as if they're attempting to bond w/ a fish will tell you that when you're trying to uh, befriend one initially you should put your hand in the tank balled up in a fist as tight as you can make it. Expect to be bitten and the tight skin on a balled up fist will help attenuate expected damage.
Some of those guys are big fans of how personable an FH can be towards whomever feeds it and their goal is to be able to reach in and have the fish rush over to be petted. To me that seems like an odd goal and one that I've never had. I've got a couple of PBass that will bite if you let them get a little hungry but that's because they're hungry. The FH bites because it''s pissed off and that turned out to be pretty limiting for me. Might be for you as well. Might not, too.
But I doubt it.