Thanks! Nope. The Oscar and the male synspillum will sometimes very lightly spar a bit... but never to the tune of any damage. Could be a little trouble coming due to the bredhori appearing to be about to spawn... I'll watch it and maneuver accordingly. But all in all, no aggression.
Skurj... it's not really black, but it does have black on it. And yellow, red/orange... even some blue spangles! I have two of them, and they are vieja melanurus... my favorite vieja species!