[Well, that's a rather abrupt transition between chipper to complain back to chipper again. His brief pause before he speaks might suggest that]

Ah, I remember that I saw jellyfish back on the shore yesterday. How unfortunate... When I first arrived, there were turtles lifting people back to shore instead.

[The turtles didn't help him per se. But unless there were like millions of turtles, it'll be impossible for them to support his weight anyway. He swam back to the surface all on his own.]

Still, hopefully you will find a more pleasant time in this world. [As pleasant as can be with the calamity situation.]