They are all eating shrimp. I never expected them to grow like this thats why I had the 300 built. It will have plenty of filtration and a constant water changer. I also have an 8' x 4' x 4' plywood tank in the works for just the bigger cats. As for the decor, it gives some of the smaller guys places to hide and the gars hang out in the plants.
As for the Alli Gar aggression.....yes lots of it. If you scroll down in the picture forum you will see him trying to swallow my long nose gar. I broke it upa nd they are both fine.