I happened to look in the tank after dark and saw the crazyest thing.It was gliding along the bottom and had the flesh of an octopus.it was superflat and had a slight backbone it was 4 inches long and an inch across and brown and dissapeared into the rock.ive never seen anything like it.i was going to catch it but it was so cool i didnt want to hurt it.it was like a sea hare without the body just flat.now im thinking what if it eats my fish or something.any help is appreciated!