I bough these last weekend. They are a few months old, maybe 2? I purchased two for my mom, but her tank is still cycling so she's unable to take hers. I've noticed today that they are starting to fight each other. They will not come out of this corner of the tank either. They just let the food come to them. I'm feeding rods food. Should I separate them? When I purchased then there were at least 40 others. I'm not sure what to do. I don't want them to become stressed. They aren't eating that much either the food just blows around the tank. It's seems like the two larger ones are doing the most fighting. But the second largest is fighting everyone.