Jack is a brainy, noisy, overly hyper male guppy. He's more likely to get swept up in the action than comment on it, though he's been known to utilize an advanced vocabulary for his age. He's best friends with all the boy guppies, who especially like to hang out with him because he's well-versed in slapstick humor. Physical activities calm Jack down, so he'd rather play "basketball" than define it. Jack has a persevering spirit. His willingness to keep trying, combined with encouragement from his friends, often leads him to triumph in the end. Jack's favorite things to do are read graphic novels and eat hamburgers.
Jack has peach skin, Nonny's-style teal hair, and brown eyes. He wears dark purple goggles for glasses, and his tail is light blue with darker blue stripes.
- Jack is a very loud guppy. It's nigh-impossible to get him to quiet down.
- HIs favorite color is blue.
- He hardly ever frowns.
- Jack is thought to be the most rambunctious guppy.