Water related names for a fictional story?

I am currenty wtiting a book about a girl. Most people think that she is a witch (a powerful one at that as she is related to one of the most famous wizards ever) but she turns out to be an elemental (one of the four in the world). She is a water element (later revealed at the end of the book) and I can't think of names for her. I think that Aqua, Aquamarine, Aquanette etc. or anything like that might be a bit too obvious so if you have any name please tell me them. Try not to make them too obvious...I think it should be descreet...