while its fascinating when fish fight, i dont really consider fighting a good trait to look for
i prefer to see them just doing whatever they do, no stress, depending on their personality.
labidochromis caureleus (sp?) electric yellow is fascinating to watch because mine seem really chilled, but extremely fascinated with everything i add or change.
if i add a lava rock, they go in and explore the floor , the walls, the ceiling, they swim out a hole then turn and look back at the hole, swim under/around/through everything and examining every inch of it closely.
other fish just go "meh" and swim on through without a 2nd thought.
labidochromis hongi.. he's a 'ranga'
i gave him a "mrs hongi" the other day, but he was pissed off about it for some reason.
his ginger/orange dorsal fin, belly, and face markings really started to glow brighter, his body colours (hes a teen -> adolescent) went from a brown to almost a skin tone pink, flared fins etc.
truely spectacular colour change depending on his emotion.