How's this for contingencies. A few weeks ago i was diving solo in 100 feet spearfsihing around a shipwreck. i had one or two small bleeding fish in a bag I had clipped to my belt.
I entered "into" a shipwreck, it was actually just a 20 feet section of wreckage that had a ceiling that was maybe 6-8 feet high and the depth of the recess was only like 12 feet. more like an overhang, not confining at all.
I went in their looking for fish, initially I was skip breathing and hoping for a fish to appear as I lay still on the bottom. Suddenly I see about a 5 foot green moray coming right for me meandering through the floor of the wreckage like a snake. It was coming fast and i instinctively tried to rise up to get off the bottom and away from it.
It followed me up and was bitting at the bag which is against my leg and not far from other important parts. I tried to back out of the enclosure and backed out a few feet, but because I was distracted by the eel I was scrapping the ceiling and i instantly became entangled on something on the ceiling with my tank. I was now stuck to the ceiling and had my hands full, I was repeatedly hitting the eel with the pole spear and I was trying not to injure it (I could have shot it with the speargun, but that probablly would have made things worse if i didn't make a perfect shot). This whole situation took less than 5 seconds to evolve.
I couldn't really move at all, i couldn't go down because the eel was really excited and pised and was biting at the spear and my bag and i couldn't move back or away because i was stuck. I kept smacking and poking the eel, quite forceably but it really wanted the fish I guess. I remeber thinking: "who would beleive this situation?". 15 seconds ago the dive was going perfectly and now I got a problem.
I decided that the eel was going to have to suffer for my stupidity, so I really began poking it hard and puncted the skin and open mouth, while i tried to avoid it's eyes. After a few really hard jabs, he finally lost interest and slithered away.
I exhaled and then wiggled and shook my tank a little and quickly popped loose from the ceiling. 25 seconds of spearfishing excitement.