hi,
I have got my 2 new Red Tiger Oscars, about 4 cm long, my Plec that I have had about a year, and a new Green Terror. The Green Terror seems to be dominating the O's, itt chases them round the tank and sims up and down against the tank, the O's do this sometimes too. I only got them on Wednesday, do you think things will settle down, or do I need a smaller Green Terror, he is the same size as the O's.

need more specs on your tank e.g tank size

thanks

green terrors are more aggressive fish than Os. even Os are bit bigger than the GT, GT might dominate the tank.

Green terrors are called terrors for a reason, they can be an aggressive nightmare. I had one a few years ago and he battered an oscar twice his size. Keep an eye on things and if they get bad rehome the terror. It might work if you have a real big tank. However all fish are different and you get a terror that is ok with your oscars but i doubt it