About a year ago I introduced a small blue legged crab to my tank. It was a bother to say the least. It killed plants that I had growing and it even killed one of my snails. Anyways it was always shy when I’d walk towards the tank and it liked to hide but I would always be able to notice it from across the room climbing on the live rock or on the sand bed. It used to climb a lot. Mostly on a tube I had starting at the bottom of the tank and going up and out of the tank for an air stone. Now I can’t find the crab anywhere and the air tube and tall plants are gone so there’s nothing to climb but is is possible it escaped? My tank ammonia levels are 0 so I don’t think it’s dead in the tank. I’ve shined a light on the LR and I see no trace of the crab. No shell or anything. But I also don’t think it got out of the tank and died somewhere because I don’t smell anything foul in my house. Is it possible the crab just comes out at night and is a really good hider? No idea what’s going on so any advice would be appreciated!