Ok I have only owned jags in a pair like I have today. I bought them at 2" each and luckily I ended up with a pair in my 125. I have never owned a Jag in a community tank etc. Now mine breed so they are crazy aggressive.... like even my hand is attacked during cleaning. They have no fear and do not back down. Although I have been told by some that if it is a lone fish like a single male in a tank with other types of cichlids then they are not that agressive at all. Is this true??? Like if I had a 265 gallon tank with a 14" male jag, could I have some mellow tank mates with him like a Oscar and a severum???? Or is this info I have way off and this guy will kill everything???