At least three of these guys managed to hitchhike into my new nano tank on live rock. I will try to get better pictures tomorrow when the lights are back on, but they look like oyster drills to me. As far as I know, oyster drills are on the Atlantic side of FL and the rock came from the gulf side. Can anyone tell me what they are and if I need to remove them? The third one (not pictured) has bright orange coral growing on him so I hope they aren't harmful!