The thing that doesn't make sense is that to deem a fish agressive, it has to be 'mean' towards other fish.
And with a 10g, there's not a lot you can do, if anything to be able to see 'aggression' from one fish to the other, unless you are mixing incompatible species and/or overcrowding the tank.
There's lots of fish that are "aggressive", but if you're only looking for one fish, then what would be the appeal to its agression? The fact that it *would* be aggressive towards other fish *if* it had tankmates... aggressive towards the walls of the tank...? Does it have to look mean?
So... what are you water parameters like and what is your definition of aggressive?
You can cram some big cichlids in there. That will give you aggression on a whole new level! But, it wouldn't be very responsible, and I wouldn't recommend or approve of doing such a thing.:duh:
by agressive i mean more of somthin i can feed small live fish to and for whoever asked me if this is my first tank no i havea 45g with 3 juvie convicts, a blue acara, and some tiger barbs
A 10g is barely big enough for feeders, much less an agressive fish which would eat them . Keep in mind that even agressive fish need to grow bigger to start eating other fish, and by that point they need something much bigger than a 10g
I'm the whoever that asked if this was your first tank. I would recommend you do some more research on "aggressive fish." You're going to find that there really isn't anything you can do in that realm with a 10g.