Thanks for the comments everyone.
bbortko, not sure I completely understood your reply but I feel I got the gist of it?..Hah.
mrrobxc, the added rocks do help with territory sometimes, however I've found they can also actually increase aggression a bit as the fish will begin claiming areas. In my case, the "three amigos" as I like to call them (pearsei, syn, and argentea) are mostly open water swimmers. Only the male C. sajica really tries to claim a particular area.
You just have to find that balance.. and less is often more.