Many years ago, I went night diving in a Florida spring...back in the day when I used to wear a snorkel. I did not know it, but there were a lot of fresh-water eels in the spring. Upon ascent, I managed to snag a rather large eel between my snorkel and head. Imagine being unable to see or know what this snakelike thing is whipping around your head at night, 50 feet down! Only thing I knew to do was stay as calm as possible, pray that it was not a poisonous snake and keep going up---. When I surfaced, it escaped. My buddy thought his dive partner had become Medusa!