Shark Tank's Mark Cuban dives with Galapagos sharks for charity

Mark Cuban is coming face-to-face with one of his greatest fears.

While the businessman is used to battling entrepreneurs on ABC’s Shark Tank, he recently braved the deep blue and took a dip with Galapagos sharks off the coast of Oahu, Hawaii, for a good cause.

In Discovery Channel’s upcoming Shark Tank Meets Shark Week special, Cuban and costars Barbara Corcoran, Daymond John and Kevin O’Leary team up with different shark-saving causes and vie with one another to award one group a $50,000 donation.

Shark Week Mark Cuban 2018
Credit: Discovery Channel

“I’ve been doing pitches my whole life,” Cuban, who has teamed up with Shark Allies — a non-profit organization that is dedicated to the protection and conservation of sharks and rays and the ocean realm they live in — exclusively tells PEOPLE in this week’s issue, on stands Friday. “Just like any entrepreneur that comes on Shark Tank, I want to get to the motivation I want to get what makes Stephanie Brendl’s organization different and how we can use the money is ways that the other organizations can’t. It’s important.

He adds, “Underwater, I was learning so much from Stephanie. There are a million plus sharks that are hunted every year – for shark fin soup, or captured by a commercial fishing organization and thrown away. It just makes no sense.”

Shark Week Mark Cuban 2018
Credit: Discovery Channel

And while Cuban gathered plenty of knowledge during his dive, he learned a great life lesson as well.

“You get a sense oh how much bigger the world is than our little piece that we have,” he says. “There’s just so much more around us. It reminds me that I’m part of something bigger.”

“I’m not a big time snorkeler so I didn’t know what to expect,” he says. “But the way they set it up was great. I got to go down to the bottom of the cage. I got comfortable within two seconds. I was just like, ‘Wow – I’m not nervous. They’re not intimidating.’ It was like, ‘Thanks for letting me in your space guys.'”

Shark Week Mark Cuban 2018

“The biggest misconception is that they’re inheritany mean, aggressive, and man-eating but nothing could be further from the truth,” he says. “This is their world. You can just tell, once you go underneath the water, it’s their world.”

  • For more on Cuban, pick up this week’s issue of PEOPLE, on stands Friday

Shark Tank Meets Shark Week airs July 25 at 9 p.m. on Discovery Channel.