Ha ha, now you got me curios, what sound would sea cucumber pooping like, squeaky, fart-y, popping...... I once saw a fish poop in mid air and the next fish went behind and eat up the poop...... makes me wonder if marine life are conscious about hygiene........ alright, I think too much 
Oh, one last thing, how do you know when the sea cucumber is going to poop? It's not like it has some sort of expression to make (do they?) I think one of my videos lack is capturing unique/interesting behavior, and your videos have lots of them. It's hard to know and anticipate when they're going to do something or strike for food. My videos are mostly staring contest with fish before either one of us swim away. Being diving in a group (as small as 2 people per group), I can't just sit there and wait for things to happen most of the time because there are other divers behind me waiting to take photos.