Overnight, it appears that my YWG and pistol shrimp may have separated. They normally occupy a burrow (and tunnels, of course) in the left side of the tank. This morning, though, the Goby seems a bit out of sorts and there is a new pile of sand under a cave of rockwork on the right side of the tank. I haven’t seen the shrimp yet (or heard the clicking) but suspect he has somehow relocated. Is that unusual? I figured his poor eyesight and bond with the YWG would’ve kept him from straying.