PEGGYS COVE, N.S. -- Sean McMullen is a treasure hunter and explorer on a mission to see what lurks beneath the sea.

An avid diver and professional photographer, McMullen calls himself an ocean janitor – documenting his findings on his Instagram and YouTube channel Saltwater Sean.

“It's a whole different world under there,” says McMullen.

“I've been to Ketch Harbour. I've been to Terrance Bay, Prospect bay, I've gone up to Isle Madam in Cape Breton,” he says.

However, one of his favourite spots is Peggys Cove Harbour, near Nova Scotia’s iconic Peggys Cove lighthouse.

McMullen and his father, Jonathan, explore the waters, bringing back a bounty of bottle booty.

“There’s lots of garbage, from hundred and hundreds of years of human activity,” he says.

McMullen has discovered all sorts of things under the sea, from an old door to marbles -- even a toilet seat.

“We found a kitchen sink here off a boat and we brought that up and recycled it as well,” he says.

The main motive behind McMullen’s project is to make waves about ocean conservancy. McMullen takes everything he finds with him to show others that what's beneath the surface isn't always pretty.

“Our earth is all we have. We've got to take care of our backyard,” he says.