wow,sounds like you have quite the aro. I have a friend with a 129 with 3 different types (1 just died) and none are that aggressive. i don't know much, but it sounds like it could also be from a lack of other interest. My friend's aro loves the plants in its tank, and eats things other than live feeders. The again, it could just be one aggressive fish. who knows, but try what you can if you want more than one fish in that tank.
