Bill
32137
We also saw a hammerhead shark which at around 40meters depth
Back in the really old days when we dove with a little less anxiety ( foolishness)at 15-20m depth till our air ran out and that was the signal to pull the reserve air which gave us a comfortable rise to the surface.
It was a steal wire on the side of the tank we pulled on to open the reserve. Yes a little sketchy and we did have some accidents but rare.
Young fellow was me. Older diver shows the equipment we had.