Keith Brock says he's gone on about 250 scuba dives since 2013 and has never seen anything like he saw Sunday. 

The Fernandina Beach man was about 30 feet below the surface with his wife and 13-year-old niece when he was an amazing sight: a whale shark moving through the water with schools of remoras and cobia (the little fish in the video).

Brock and his family were off West Palm Beach doing what they just love to do: dive and look at marine life. He says over Facebook messenger he never thought he'd run into something like this.

Watch the full encounter on YouTube below:

While it may be frightening to look at, it's important to note whale sharks mostly just eat planton; they don't have a desire to eat anything bigger - they filter feed. The other fish around it are sharing in the symbiotic relationship. Remoras eat parasites, bacteria and dead skin on the whale shark's skin, getting rid of those unwanted things for the shark while attached.

Brock says no one was scared on the dive; all those fish are friendly. He also said that he and his fellow divers never harrass marine life and just enjoy the dives and looking at the fish they encounter.