I would not worry about a nicked fin. If the damage continues or you see more aggression, then I would consider removing one. Are you sure they are damaging each other? Most of your other fish are capable of tearing a fin.
Those texas should be pretty spoiled. I don't think they'll fight since you've got a community in there with them and some landscaping. But, just keep your eyes on them cause they look too good to be picked on.
Well, it looked like it would work at first, but one of them suddenly became more aggressive, and was displaying for and attacking just about every fish in the aquarium. I moved that one to a 55 for now.