I could get into exactly what's going on here, but you can see that in the video. There are SO MANY hilarious things about this. The fish getting slurped into the tube and then *NYOOM* to the other side. Notice they put that sucker in right side up but it got YEETED out the other side upside down.
It's like someone went to an environmental scientist (or whomever's job it was to come up with this) and asked, "how can we solve this problem in the funniest way possible?"
Salmon cannon.
SALMON. CANNON.