H₂O: Just Add Water/Characters

Cleo Setori, Mermaid of Waves
 * Naive Everygirl
 * Nice Job Breaking It Hero: Charlotte probably wouldn't have gone over the edge if Cleo hadn't been so hostile to her.

Emma Gilbert, Mermaid of Ice
 * Control Freak
 * Put On a Bus: in season 3.
 * The Smart Girl: Probably the smartest of the three mermaids. Also often "smart" as in sensible.

Rikki Chadwick, Mermaid of Fire
 * Deadpan Snarker
 * Missing Mom
 * Tomboy
 * Tsundere

Lewis McCartney
 * The Smart Guy

Zane Bennett
 * Jerk With a Heart of Gold
 * Lonely Rich Kid
 * Slap Slap Kiss: with Rikki.

Louise Chatham
 * Cloudcuckoolander

Byron
 * Brother Chuck: Disappeared after Season 1 with no explaination.

Miriam Kent
 * Alpha Bitch
 * Brother Chuck: Same as Byron.

Charlotte
 * Clingy Jealous Girl: The reason for her hatred of Cleo, which automatically puts her at odds with Rikki and Emma as well.
 * Easily Forgiven: The girls seem to get over the fact that she spent almost an entire season hating their guts and trying to hurt them whenever possible rather quickly.
 * Evil Redhead: At first.
 * Heel Face Turn