Fishtales

Fishtales is a 2007 movie is featuring a mermaid Neried played by Kelly Brook.

Plot
Greek-History Professor Thomas Bradley and his twelve year old daughter Serena, go to Greek island Spetses to look for inspiration about his work. Serena tries to match her father with local women, but to no avail. After Serena meets Neried, a mermaid, she thinks she has found a perfect match for her father. Captain Mavros finds out that there is a real mermaid on the loose and wants to catch her for the jewels on her tail by any means necessary. Eventually, Nereid sacrifices her immortality to be with Thomas and his daughter and they move to America.

Links
Fishtales page on IMDB