Ohhh... something I forgot about completely until reading Steve's post is that if you believe they will not be aggressive towards each other and decide to keep them together, you should have plants (fake or real) in the tank to break up the line of view. That way they have places to go to not see each other, kind of like their own private hangouts. But you shouldn't keep them together if there are any signs of aggression towards each other.
I remembered Steve posting that a while back about the plants, which is why I remembered it after I read Steve's post.
