It's "humane" in a circular tank with appropriate care and food. Obviously marine water. Bc they don't have the same nervous systems we do they're not aware of boredoms or stress like higher organisms are susceptible to.
There are blooms of jellyfish happening everywhere now. Here in Newfoundland in the bays where fresh meets salt water there are literally millions of jellyfish now, comes and goes.
They're thinking it's caused by the pollution and disruption in ecosystem due to over fishing. (ps, I didn't read the full article) I think they're neat.