Unless you're a hoarder, a Seattleite or a character on "Breaking Bad," you probably store actual cars in your garage. Fiona Lewis and her parents are none of the above and yet when Lewis was a child living in Melbourne, Australia, her family's garage was typically filled with ... fish tanks.

"My parents had a garage, which in theory could have fit six cars, but in practice didn't have one," says Lewis, 42, now a District resident. Instead, her father used the garage to breed and grow various fish that had become endangered in Australia, including the Murray cod, the largest freshwater fish in the country.

Her father Ron's devotion to repopulating endangered species — a completely volunteer gig  — was just one of many influences that shaped Lewis's perspective on the sea and the creatures that populate it. As a child living in Victoria, a coastal state on the southeastern tip of Australia, Lewis was practically surrounded with people invested in the fishing culture. One of her great-grandfathers was a fisherman; so were both of her grandfathers. Her parents, after Lewis had left the nest, started their own fish farm raising golden perch.

"My father was very involved in wanting to repopulate" Murray cod, Lewis says during a phone conversation. "That’s certainly where I got my passion for sustainability.”

Come November, Lewis will have her chance to put her passion on display with the latest addition to Union Market: the District Fishwife, a 440-square-foot seafood market and cafe that will deal in sustainable fish. Lewis is expected to sell locally sourced products — rockfish, blue crabs, oysters — while working with distributors and wholesalers to find sustainably caught tuna, wild salmon and sustainably farmed barramundi. She also wants to push small, oily fish.

"I’m very passionate about sardines and smaller fish — fish that are lower on the food chain," Lewis says.

Following the lead of almost every vendor at Union Market, the District Fishwife will offer prepared meals, a practice so common at the venue that one former pop-up operator dubbed the place an upscale food court. But Richard Brandenburg, director of culinary strategy for Edens, which develops Union Market, says that sales of seafood glass-noodle salads, fried calamari and fish and chips (with house-made tartar) will keep the District Fishwife as viable in the years to come as the seafood it will sell.

"If we’re doing both at the same time," Brandenburg says about prepared food and fresh fish, "it will be more sustainable.”

Lewis is a relative newcomer to the District. She moved here four years ago when her husband, Benjamin Friedman, took a job in Washington. Lewis is a newcomer to the fishmonger business, too, though she's quick to note that she has plenty of experience, both front and back of the house, in restaurants, including a fine-dining seafood establishment in Melbourne.

At the urging of a friend, who was contracting for the U.S. Agency for International Development, Lewis even helped open and manage a restaurant in Afghanistan, where she might have landed the biggest catch of her life: her husband, who was working in the country as well.

Now she wants to bring all of her experiences together to help give Washington a taste of something she feels is in short supply here: a full-service fish market that helps customers select, cook and store their seafood at home, much like those fishmongers at the Queen Victoria Market that Lewis frequented back in Melbourne.

"I noticed when I came to D.C. a lack of seafood markets, especially a lack a seafood markets in Northeast, where my husband and I live," says Lewis, now a U.S. citizen. "This is fresh food, more like the markets I’m used to."