I awoke this morning to find my "black mystery snail" floating in my tank. His little snorkel was out and he apeared to be alive but he just floated there. I tried to submerge him but he kept popping right back up. I took him out and placed him in a cup of water to keep the gouramis from eating him. He adheared to the side of the cup so I figured he was ok. Tried to put him back in the tank, just to have him pop right back up to the top and float again. Weird huh? any comments or suggestions?