Idea's for an ocean themed tattoo sleeve?

I'm after ideas for an ocean themed tattoo sleeve (not reasons why I shouldn't get one, my dads a tattooist and I'm an apprentice tattooist so it's definitely something I love and have thought about) I'm 18, female. I chose an ocean theme because basically there's nothing I love more. So far I'm thinking, anchors, shells, perhaps a mermaid, starfish.. What else do you think would look great in it? Please keep in mind I'm a girl ;) thanks.