Putri Duyung Marina

Putri Duyung Marina (Marina the Mermaid) is an Indonesian fantasy-drama sinetron that starts out with shades of Dyesebel and the Hans Christian Andersen story. Marina, a mermaid, is born to a human father and formerly-mermaid mother Arumi (Vista Putri), and is given to the sea where is raised by Riska (Lia Aulia) under the command of the strict Queen Asoka (Anastasia Novie) who rules over the merfolk. As a young woman Marina (Dhini Aminarti) sees a handsome human man named Rendy on the shore, falls in love, and there's a rescue in there, but afterwards Queen Asoka's daughter Princess Tiara (Kylla Nuraver) attempts to take credit for the rescue as she is also in love with Rendy.

I can only seem to find the first full episode online so I can't comment on the series as a whole, but my impression is that there's multiple storylines in the show, making Marina's love adventures are only one of them. Marina and Tiara venture on land, while there's a major plot of Queen Asoka battling other magic-wielding characters. It all looks super melodramatic and at times harrowing, from the few clips I've seen. In the first episode at least there are some brief underwater bits, but with basic CGI tails and the like.