there is no real single aggesive fish. Jars are not good with tankmates dovi get big and are CA/SA cichlids and they are all for the most part not nice but dovi have size behind them. RBPs are pretty common and cool but it's not like I worry about sticking my hand in my tank. Most of the wolf fish I have seen for sale will not get very large.
So it's more of a question what do you want
teeth
color
Reputation
and what size tank do you have. I mean if you want a NASTY fish get a gator gar but you best have over 1K gallons for it. but if you got a 55 then get 3 RBPs b/c they won't outgrow the tank. If you want nasty teeth get a armatus but again they are from what I read skittish so you need a large tank to try to keep them from killing themselves after running into the glass.
a few things to think about.
So it's more of a question what do you want
teeth
color
Reputation
and what size tank do you have. I mean if you want a NASTY fish get a gator gar but you best have over 1K gallons for it. but if you got a 55 then get 3 RBPs b/c they won't outgrow the tank. If you want nasty teeth get a armatus but again they are from what I read skittish so you need a large tank to try to keep them from killing themselves after running into the glass.
a few things to think about.