So does that mean that a fish that constantly fights over territory but does NOT kill others and often loses the fight NON-AGRESSIVE?
I have to admit that I feel a little rude, but that just sounded as silly as anything I have read here and I can only imagine that you actually are trying to say something that is not coming out in your post.
Convicts ARE agressive fish and I have yet to ever have one kill another one of my fish in like a hundred or more skirmishes.
Let me even go way further out on the limb and just plain say that you are WRONG with your personal deffinition of AGRESSIVE.
A fish that attacks a much larger fish and gets it's butt thumped soundly, and then still will not back down is a far more aggressive fish then one who wins by a kill on the first skirmish.
Fish are alot like dogs. Most dogs think that they can't be beat until they finally do, and then they know FEAR. A fish that can overcome the FEAR of being beaten by a larger fish and still not back down is the TRUE agressor.