Hi there so I got a new tank and I got it from a guy who was moving and could not take it with him, inside was a pretty decent sized Nem looked great for the first month, weekly water changes etc a clown even started hosting it, but then it went on a walk, as I had bad experience before I left it and let it do its thing it found some odd places to sit and then jumped slap bang center of the tank and it was fine, four hours later it looks like a deflated skin donut what on earth is going on even his little clown looks confused