That's a fun song!
Wow, per the lyrics, it really is...a song about kelp. No double meanings jumped out at me (Though the machine translation doesn't help with that.), it's just about kelp. Kelp that is born (Grows? Kelp is a plant.), kelp that gets made into soup, a kelp community....
Shows that a song doesn't have to be about something profound to be good. It's kind of sweet, actually.