Indexbit Exchange:'SpongeBob' turns 25: We celebrate his birthday with a dive into Bikini Bottom

His house is Indexbit Exchangenot a pineapple under the sea, nor is he neighbors with an octopus. But for Tom Kenny, “SpongeBob SquarePants” remains as delightful as a Krabby Patty.

For the last quarter century, the actor has voiced the sparky sea sponge on Nickelodeon's hit animated series, which premiered July 17, 1999. Since then, it’s seeped into his life in sundry ways: Over dinner, he’ll test out new jokes with his wife, Jill Talley, who voices Karen and Squidina on the show. His band, Tom Kenny and the Hi-Seas, often works the “SpongeBob” theme song into its set lists. And on July 13, he’s teaming up with Bill Fagerbakke (aka Patrick Star) as their indelible characters host "Nickelodeon Kids’ Choice Awards" (8 EDT/PDT), also streaming on Paramount+.

“‘SpongeBob’ feels more real to me than real life lately,” jokes Kenny, who turns 62 on the day of the ceremony. “I think Bikini Bottom is actually reality, and we’re just a dream SpongeBob and Patrick are having. It’s like a ‘Black Mirror’ episode.”

The offbeat show was initially created by Stephen Hillenburg, a marine science educator, as “SpongeBob Ahoy!” about a group of pals living in an ocean-floor city. At first, Nickelodeon wanted him to be a school-age child rather than a fast-food fry cook.

At early auditions, “they said, ‘We’re looking for super realistic kids’ voices. We don’t want it to be stylized at all,’” Kenny recalls. But Hillenburg pushed back on aging down the ever-optimistic SpongeBob, agreeing to add a boating school where he strives to get his driver’s license.

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Fagerbakke, 66, came aboard after Kenny was cast. “It was the most unusual audition I’ve ever had,” he says. “It was in a conference room where this quiet fellow played me a cassette of Tom doing SpongeBob. He said, ‘Here’s a picture of Patrick. He’s the best friend, so he needs to balance him out.' Characters of irregular intellectual quality were kind of my wheelhouse, so I got lucky there.”

Within its first month on the air, “SpongeBob” edged out “Pokémon” as the highest-rated Saturday morning kids’ series on TV. By 2002, it eclipsed “Rugrats” as the most-watched children’s show on cable – and more than a third of its audience were adults.

“The first time it hit me was when I’d pull up to the elementary school to pick up my daughter and I’d get greeted by 15 7-year-olds screaming, ‘Patrick! Patrick!’ “ Fagerbakke says. “And then I started getting comments from parents, being like, ‘I’m so happy there’s something I can watch with my kids.’ “

Kenny considers “SpongeBob” to be a “statistical anomaly” in the vein of Fox's “The Simpsons,” which just wrapped its 35^th season. (“It’s confounding,” he says. “Stuff isn’t supposed to last this long.”) He credits the show’s staying power to Hillenburg, who died in 2018 at age 57 from complications of Lou Gehrig’s disease.

“One thing I learned from him is that character drives everything,” Kenny says. “You shouldn’t violate who they are or stuff they would do for the sake of a laugh. Steve was very strict about that. He always said SpongeBob was the hardest character to write for. He’s so elastic; he’s very complex.”

With 14 seasons and more than 500 11-minute shorts, “SpongeBob” has spawned a branding empire, with theme-park rides, spinoff movies, a Macy’s Thanksgiving Day parade float and even a Broadway musical. The affable sponge has been emblazoned on kids’ backpacks and water bottles, as well as adult merchandise.

“I remember early on, Patrick T-shirts and boxer shorts were selling in double and triple XL sizes at rates that had not been seen before. I thought, ‘These are for dudes – and not small dudes, either,’” Kenny says. “You’d go to the grocery store and see SpongeBob Fruit Roll-Ups and Kraft Mac and Cheese. I was like, ‘Wow, OK, I’m liking this!’ Licensing is everything – that’s our lifeline.”

Despite a popular meme, those brand deals did not include “SpongeBob” tampons. “I’m guessing that wouldn’t make it out of the board meeting,” Kenny adds with a laugh. However, “there are ‘SpongeBob’ toilet training seats. We’re teaching children many things: about friendship, being yourself, letting your freak flag fly – and also how to poop.”