What do you do with a hulking former brewery that sat empty and dilapidated for almost two decades? If you're the team behind Urban Organics, you turn the old Hamm's building on St. Paul's east side into a home for your aquaponics "farm." And there you grow healthy food in the city, year-round despite a climate with one of the shortest growing seasons in the country. Aquaponics is a self-sustaining symbiotic system in which plants and fish co-exist. Fish waste fertilizes the plants, and the plants in turn filter the water the fish live in. The system can produce certified organic vegetables using less than 2 percent of the water used by traditional farming methods. The decision to locate the business in the former brewery is also a symbiotic one: The site has access to the naturally occurring wells that were used to produce beer. They now fuel the farm. The business supplies produce to local supermarkets and co-ops, while the fish go to area restaurants. Urban Organics is currently working on its second facility, in St. Paul's former Schmidt Brewery.