By Ted Scouten

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FLORIDA KEYS (CBSMiami) — The search continues for a scuba diver who went missing near Alligator Reef off Lower Matecumbe Key.

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The crew of The Pisces contacted the Coast Guard around 5:15 p.m. Tuesday and reported that 37-year-old Rob Stewart failed to return from a dive.

The Coast Guard immediately dispatched two boats and a helicopter to the area. The U.S. Navy, the Florida Fish and Wildlife Conservation Commission and Monroe County Sheriff’s Office also sent boats to assist in the search.

According to a GoFundMe page, Stewart was diving around the “Queen of Nassau” wreck.

A friend told CBS4’s Ted Scouten that Stewart was with two other men and was ready to get out of the water.

“He dove three times on this wreck, and on his third dive he surfaced, gave the OK sign to the boat and then they didn’t see him again,” explained Julie Anderson.

Friends said the people on the boat were attending to someone else who was having a medical problem when Stewart disappeared.

They wonder if he was taken away by the current.

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They’re holding out hope because of the gear he was wearing.

“He was wearing a dry suit, which means water was not touching his skin,” Anderson said. “And dry suits also are filled with air, so if he was on the surface and it was inflated, that would have meant that he actually kind of had like an air bubble around him.”

Stewart’s sister said he was in the Keys to shoot an installment of his “Sharkwater” documentary series.

Friends told Scouten that Stewart’s passion is to save sharks.

But aside from his passion for conservation, he’s an experienced diver who does not take reckless chances.

“He’s been in all kinds of situations, all kinds of water temperatures,” Dustin Titus said. “Sharks, whales, you name it, he’s been underwater with them.”

Now they’re urging anyone who can help to join in the search.

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“Everyone’s super concerned about trying to find Rob right now. We’re all doing everything we can to get the world’s diving community engaged right now so we can get as many search efforts as possible to try to find him off your coast,” Titus said.

Ted Scouten