Hi, so this morning I found my fire eel out in the open belly up and it looked like he swallowed a marble. The lump is in the middle of his body and seems to be buoyant. I put him in a hospital tank and he just can't seem to sink he is just thrashing all over. So do I just have to wait it out until he goes to the bathroom or do I need to give him a fish laxative or something?