Awesome shrimp. Great behavior. I ahd 6 in my previous tank. Hardly ever saw them except for when I would add the sar fish to the tank. It is like they could smell it the moment it hits the water. They may become very territorial as they pair up or when eating. I quickly found that if I added the starfish alive and whole, the pair that would get to it first would not allow the others to come near it while they were eating, which pretty much lasted days or passed a week until there was nothing but a carcass left. After discovering his, I started to cut the starfish into 6 pieces and throwing them in different areas of the tank so they could all eat.
I would love to get a few pairs again in my new tank, but given how little I saw them before, I may just get a single pair for my smaller cube.