love your Geos.
your tank is similar to mine, but I have stayed with plants on the drift wood. I have had a time finding eartheaters, was hoping for Geophaygus Tapajos as they are smaller but stumbled on a heckli(sp?) locally. now I need another, I love this fish.
I had a couple angels in my tank but the geo kept them herded in the upper corner by the filter outlet, I am thinking another geo in the tank will help keep the one I have distracted as I see yours don't bother with your angels at all.
I also have rainbows and headlight tetras in this tank.
Big Tank, what would you do?
Yes, I do think it's the group that keeps them from harassing the other fish. I can count on one hand the number of times that I've one chase after a fish that wasn't another Geo...And that was all just a quick dart towards them during feeding time.
As you can see in the video they do harass each other quite a bit, but not to the point where it's a problem. All of them, EXCEPT for the dominant male(or female) have slightly tattered up back fins from picking on each other. Nobody messes with the dominant fish so he has perfect fins.
Here's a decent iPhone picture of him/her.