A quite charming, live-action German language little mermaid movie was brought to my attention called “Die kleine Meerjungfrau” (The Little Mermaid) based off of the original Andersen fairytale. Zoe Moore stars as Undie, the titular character of this reimagined classic, with pretty underwater (!) scenes! 

http://www.youtube.com/watch?v=iDX7aEI6v1o