Yes mine too which makes me wish I did a FOWLR/Mantis display tank with maybe a few softies. I could place him and his rock into my display now, but there is a sally lightfoot crab in the display with a cleaner shrimp. The scooter blenny might also have issues with the mantis. At this point he is in a 5.5G. The video was a compilation of about 14 minutes that I filmed him when I wasn't in the room.
Side note on video. I tried my Flip Camera and my Cannon for video, but the iPhone came out the best. The other two were extremely blurry. The iPhone wil be better if I can get a better distance from the mantis. I also don't like the substrate of just using crushed coral. I think the better idea is to use a mix of crushed coral and aragonite.