Steve Jackson is the most popular fish that attends Freshwater High.
Steve is a kind, forgiving and nice guy who enjoys impressing girls and being cool.
Steve Jackson first spoke when Oscar needed a new roommate. Clamantha was rejected several times when she disguised herself as different stuff. So, she disguised as Steve Jackson to be roomates with Oscar. When Oscar was about to accept him, "Steve Jackson" spat out a large pearl. It was, of course, Clamantha ("Dances with Wolf Fish").
When Milo asked the boys what the most radical-est thing they could think of was, Steve Jackson said rock and roll. When Milo needed to see what the girls were planning for their float, he hired Steve to spy on the girls, due to his irresistible looks. When Finberley was gettting glitter from her locker, Steve said hi to her. Finberley was surprised that Steve Jackson knew her name, and Steve helped her carry the glitter for her. When Finberley and Steve got back to the girls, who were working on their float, Bea's eye caught Steve Jackson. Finberley told Bea that Steve carried the glitter for her. However, Bea was suspicious about why Steve wasn't with the boys, and Steve remembered Milo's notecards he gave him, so he read one, and asked to see the girls' float. Bea asked Steve if Milo hired him to spy on their float. Steve admitted that he tried to spy on them, so Bea had to ask him to leave ("Fish Floaters").
Bea was on a date with Randy Pincherson. After she was embarrassed by Shellsea and her other friends, and said that it couldn't get any worse, Steve Jackson showed up and Bea started hyperventilating. Steve said that he wanted to have a deep conversation about Bea's feelings with her, but he saw that she was on a date. Bea tried to say that she wasn't on a date, but Randy proved otherwise. Steve then left, saying that he could find another girl to have a deep conversation with, saying hi to Finberley ("Diary of a Lost Fish"). When the students went to a field trip to Pupu Goodtimes amusement park, Bea bumped into Steve Jackson, who told Bea that he could maybe later ride a rollercoaster with her. When Bea looked back, Steve was gone, so she spent her whole day in the park looking for him. First, she looked in the House of Mirrors, but Steve left before she could find him. When Shellsea encouraged Bea not to give up looking for Steve, Bea went to the Pu-Panator rollercoaster and finally found Steve him. She sat right next to him on the ride ("Good Times at Pupu Goodtimes").
In the "Potatoes for Winter" play, Steve Jackson played as the prince who Beastapus turned into after true love with Bea broke the curse. At the end, the prince and Svetlana get married ("Fish School Musical"). When the gang decided to trick-or-treat outside the tanks, Steve Jackson joined Oscar's plan. Steve's costume was a shirtless werewolf when it's not a full moon, in which the girls sighed happily when seeing him ("Halloween Haul"). Steve is shown again in "Hairanoid" to be extremely popular at Freshwater High. He won the dodgeball game, got great grades in French class, and went on dates with lots of girls. When Oscar, Milo, Jumbo Shrimp and Albert Glass wondered why Steve was so popular, Steve walked past them, saying hi, but accidently dropping his hair gel from his backpack. While Steve didn't notice, the boys stole the hair gel and put it on their hair, making them perfect at school. At the end, when Milo, Oscar, Jumbo and Albert were all fighting over Steve's hair gel, Steve found them, asking if it was his hair gel. The boys confessed what they did, and Steve told them that nobody is perfect, and that if you try your best, good things will happen. Steve forgave the boys, and they all went to get food at the Hokey Poke. Before they left, they saw Mr. Baldwin, who had Steve's gel all over his hair, much to their horror ("Hairanoid"). In "Fish Prom" Steve was a catcher in softball, and once it was Bea's turn she got nervous about asking Steve to the prom, so she pretended she had cramps. But once another girl was about to ask Steve, Bea beat her up, and Steve suggested that he and Bea should go to prom together. At prom, Steve saw a big spill of punch and wanted to clean it up, so he went into the janitor's closet to get a mop. Finberley put a bunch of chairs in front of the door when he was in there, and he was locked out for the whole episode (Fish Prom)
- Nearly all the girls have a crush on him like Shellsea, Finberley and Koi.
- Like Shellsea, Steve has a "handsome face" while Shellsea has a "disco face".
- He once dated Shellsea.
- He is one of few fish who does not have a bumpy tail.
- He has had one major role in "Hairanoid", when Milo, Oscar, Albert Glass and Jumbo Shrimp were jealous of Steve due to his good looks.
- His name is an allusion to the Atlanta Falcons running back Steven Jackson.
- He is good at gymnastics and lacrosse.
- In "Fish Flakes", it’s revealed that he has two butts.
- He thinks dates are cool.
- His favorite color is blue.
- He has a twin in Flip Flop Island named Steve Mahalo.
- Steve's name is a reference to the Australian football player Steve Johnson.
- In “Assignment: Babies” it’s revealed that he loves babies.
- In human form, Steve resembles Jeremy from Phineas and Ferb.
- "Bea Stays in the Picture" (Non-speaking cameo)
- "Fish Sleepover Party" (Non-speaking cameo)
- "Fish Out of Water" (Non-speaking cameo)
- "Doris Flores Gorgeous" (Non-speaking cameo)
- "Happy Birthfish, Jocktopus"(Non-speaking cameo)
- "Queen Bea" (Non-speaking cameo)
- "Funny Fish" (Non-speaking cameo)
- "Baldwin the Super Fish" (Non-speaking cameo)
- "Dances with Wolf Fish" Clamantha in Disguise
- "Milo Gets a Ninja (Non-speaking cameo)
- "Dropsy!" (Non-speaking cameo)
- "Big Fish" (Non-speaking cameo)
- "Dollars and Fish" (Non-speaking cameo)
- "Fish Floaters"
- "Peopleing" (Non-speaking cameo)
- "Milo's Big Idea" (Non-speaking cameo)
- "Mascotastrophe" (Non-speaking cameo)
- "Diary of a Lost Fish"
- "Good Morning, Freshwater" (Non-speaking cameo)
- "Good Times at Pupu Goodtimes"
- "Fish School Musical"
- "Halloween Haul"
- "Fish Talent Show" (Non-speaking cameo)
- "Banned Band" (Non-speaking cameo)
- "Send Me an Angel Fish"
- "Milo and Oscar Move In"
- "All Fins On Deck" (Non-speaking cameo)
- "Fish Prom"
- "Live at the Hamsterwood Bowl"
- "Labor of Love"
- "Pool Party Panic"
- "Surfing the Interwet"
- "The Big Woo"