Isabella Hartley

Isabella "Bella" Marie Hartley is one of the main characters in H2O: Just Add Water. Bella discovered her powers after her trip to Scattery Island. She is portrayed by Indiana Evans.

Background
When Bella lived in Ireland, she befriended another young girl named Amelia Clark. They became mermaids together at Scattery Island. Some time later, Melia (as Bella called her) grew fatally ill and was on the brink of death. Bella then discovered that she caught a mermaid illness, which would kill her if she wasn't taken to the place where she transformed on a solar eclipse or fifty-year full moon. There, believing that if she swam in the moon pool her friend would be cured, Bella pushed Melia into the pool. One miscalculation that she failed to notice was that Melia was taken to Eva's time, instead. In tears, Bella then dove into the pool to save her, but her attempts were in vain and she also sacrificed her freezing powers in the process. She takes off her own necklace and replaces it with Melia's, to keep her memory. Bella, however, was blamed for her friend's so-called "death", leading her to flee Ireland.

Personality
Bella is a bit withdrawn and sensitive because she's a mermaid, meaning that she can be afraid to reveal herself, but cares deeply for her friends (especially Will Benjamin, because of her feelings for him). Bella is also described as being a bubbly ball of energy that is easy to talk to. She enjoyed walking around in Ireland fields while her parents were both at work. Later she became a fun loving girl with her new two friends.

Appearance
Bella has blonde hair that cascades down past her shoulders. It appears to be a naturally wavy texture, as evidence when she wears it loose. She often styles it by braiding it to the side. Usually, she wears it down though. Bella's eyes are ocean blue, and she has a bronzed complexion. She is not quite as tan as Cleo Sertori but not as pale as Rikki Chadwick and Emma Gilbert. She appears to be the shortest of the mermaid trio. Bella has a slim yet curvaceous figure. Out of all the girls, she wears dresses the most. She wears colors that reflect more earthy tones, such as greens, blacks, and flowery designs.

Bella, with the other five mermaids, is never seen without her signature blue necklace (which is revealed to be Melia's, later on). Along with this, she wears a locket identical to the others', but with an amethyst stone to symbolize her powers. She wear her locket and necklace every day by switching them ever so often.

Becoming a Mermaid
Bella became a mermaid when she was nine years old. She was with her parents in Ireland, but they were too busy at work, so she explored the area with Amelia. They found a sea cave. When they jumped into the pool on a full moon night, she was transformed into a mermaid. Bella and Amelia found dark blue crystals at the bottom of the moon pool where they became mermaids. They tied these crystals on brown strings and Bella has been wearing Melia's ever since her disappearance.

Mermaid Powers
Bella possesses the ability to transform into a mermaid ten seconds after she touches water. Once her body is completely dry, she turns back into human along with the outfit she was wearing before the transformation. She has the ability to swim at super speed of 600km/h, hold her breath for more than fifteen minutes, and dive at a depth deeper than any ordinary human-being is capable of.

Gelidkinesis
Bella has the ability to transform water and all things that contain water into a jelly-like substance. Bella also shows the ability to change its viscosity. Bella is shown to control the duration of her power's effect.

Substanciakinesis
Bella also has the ability to transform water and all things that contain water into a substance similar to crystal or glass. Bella uses this power to create stepping stones, to cross a river without getting wet, and to transform the sculpture that Cleo was molding with her power for Rikki's birthday present. Bella is shown to control the duration of her power's effect.

Will Benjamin
Bella develops a crush on Will almost as soon as she moves to town. Because he is often curious about what he "thinks" he saw, Rikki always tells Bella to stay away from him to keep their secret safe. As they become closer, Will starts to have feelings for her. On one occasion, he accidentally dripped water on her chin and she is forced to run into the ocean before she transformed into a mermaid. Will then becomes suspicious of her and pours a glass of water on her hand, forcing her to transform in front of him. Although shocked at first, he agrees to keep her secret (though she keeps Cleo and Rikki's identities a secret).

However, Bella often hears Will talking about mermaids and the magic of it, and begins to feel that he is only interested in her because of her mermaid magic and breaks off their friendship. Eventually, they become friends again after Will finds out that Cleo and Rikki are mermaids as well. In one episode, she mistakenly hears Will asking Rikki to a party and decides to go with Nate to make him jealous. At the party, they clear up the misunderstanding and officially become a couple.

Trivia

 * She was turned into a mermaid in the Scattery Island, unlike Cleo, Emma, and Rikki, who turned at Mako Island, and Natalie and Andrea, who turned at Sirena Island.
 * Her favorite color is green and wears clothes based on gemstone colors, similar to her power.
 * Due to Bella moving every year, it is unknown what country she is from; despite this, it is most likely that she is Australian or Irish.