They shouldn't, but I remember one member a while back who had this problem and removed the BH.
All characins have the ability to nip, since they have some excellent sets of teeth. The larger the group of most species, usually avoids this. But there are some species to whom angelfish would be like waving a red flag in front of a bull (Serpae Tetra for instance).
I have BH in my 115g, and I have never observed any attempts to fin nip. Now, I don't have angelfish in there, but I do have a Bolivian Ram and some long-finned sedate tetras and hatchetfish.
Eight is a good number; I started out with that, sadly lost three to a protozoan infestation, but my remaining five are behaving. But they remain in the group with the Robert's Tetra which are closely related, so it may all seem like one happy family to them.