I got ghost shrimp a couple days ago, they only had 3, so I got all 3. They were fine and happy but i wanted just a few more. Then went to another petco the other day and got 3 more. They're neat and fun to watch, and my tank had grown lots of moss and my plants came with insects that were killing them so it seemed like a good fix. This morning I turned the lights on and one was on the other! I immediately thought it was hurting the other one, but wondered....maybe they're reproducing?? But nope, I have a murderous ghost shrimp. He got 3 of them. The survivors are in my 2.5gal now instead. So, im wondering... Is this normal behavior? Do I have to worry about this with blue velvet shrimp? What do I do with the bully shrimp? Maybe give him back to petco? He was fine in their tank im guessing. Evil little cannibal.