A tilapia garden grows in LondonderryBY KATHLEEN D. BAILEY
Special to the Union Leader August 31. 2017 12:16AM
LONDONDERRY — When Ross Williams feeds his fish, he doesn’t sprinkle a couple of flakes from a small bottle into a 10-gallon aquarium. He mounts a ladder and dispenses a large scoop of fish food into a tank the size of a Jacuzzi. And the 2,000 tilapia he feeds return the favor by fortifying his plants with nutrients.
Williams, a native of New Zealand, is exploring and perfecting the technique of aquaponics in a facility off Brewster Road in Londonderry.
Williams came to America from New Zealand for the same reason Americans move “Down Under”: adventure. He was raised on a farm and came to a place in his life where he felt he needed a change. He got a job on an American tuna boat and “a week later, we sailed for the States.”
He settled in Massachusetts, working as a parking lot manager and landscape contractor before finding a career with Apple Computers. He met his late wife in Massachusetts and they married.
Williams and his son, Gavin, began experimenting with aquaponics in their home. “It seemed like an interesting thing to do, to grow plants and fish together,” he said. When Steve Jobs died and other changes came to the computer industry, Williams decided he’d “had enough of corporate life,” and went full-time into aquaponics, buying a parcel of land in Londonderry. He moved to New Hampshire five years ago. Today, they run Victory Aquaponics.
Williams defines aquaponics as a combination of aquaculture, the raising of fish, and hydroponics, the growing of plants in water. In traditional aquaculture the fish are fed and raised in large ponds, and the water has to be flushed out because it’s saturated with ammonia, Williams said, relaxing in his office. And in hydroponics it’s necessary to use chemical fertilizers.
But in aquaponics, the fish provide the nutrients for the plants, through the food they are fed and excrete, Williams said. These nutrients include iron, magnesium and calcium. “Through nature, these are fed to the plants,” he said.
“The fish provide the nutrients, and the plants clean the water for the fish,” he explained. “Beneficial bacteria” turn the ammonia into nitrites, and another beneficial bacteria turns the nitrites into nitrates, he said.
“This is the way nature wants to do it,” Williams said. “We think we can do better, but we mess it up.”
One fish, two fish
Williams has a small system set up in his office and reception area to demonstrate the concept. Fourteen large goldfish swim in a 40-gallon tank next to a wooden stand holding trays of plants. The first system is a “flood and drain” system, in which the bed for the plants contains a planting medium. In this case it’s “pumice rocks’ made from recycled glass. “The water fills up the base and is automatically siphoned out,” Williams said.
The second system is a “deep water” system. The plants are suspended above water, each in a hole on a wooden board, and the roots go into a bin of clear water containing the nutrients from the fish. “The plants are suspended above the water, they’re not in the waste material from the fish,” Williams explained. He keeps the plants above water with a “grow-grip,” a small two-sided holder made of polyethalene.
Special LED lighting can be switched to different colors, depending on the plant and the need. “White, red and blue are the colors,” Williams said. “They don’t need any green, they’re already green.”
He led the way past a small tray of bok choy seedlings ready for “planting,” explaining how he would rinse the dirt off, place them in a grow-grip and suspend them in the water.
Williams keeps his fish in the basement of the facility. Most of the fish he raises are tilapia, with a small selection of goldfish. “I have 2,000 tilapia at any given time,” he said.
The sound of water feeding the giant tanks is a constant backdrop in the basement room.
The top-floor greenhouse is as warm as traditional greenhouses. Lush plants protrude from the boards in the deep-water method, including bok choy, red leaf lettuce, mustard greens and kale. This technique works for shorter plants, Williams said.
He uses a planting medium and individual pots for taller plants such as tomatoes, he said. “They need the planting media, to keep them upright,” he observed.
He pointed to a red and black ladybug, a spot of color on a flat of greens. “We release a few of those, to make sure they keep out the ‘bad guys,’” he said with a smile. The “bad guys” are the bugs and other pests that could plague a plant. He does not use bug spray or other pesticides.
In addition to several varieties of lettuce, he grows kale, basil, cilantro, parsley, cucumbers and tomatoes.
He could grow root vegetables, but it is time-consuming, Williams said.
Where to find him
Williams and his staff, including Gavin, Dalton Hart and greenhouse manager Natalie Cross, now truck produce to the Derry summer farmers’ market and the year-round Salem Farmers Market. They also supply produce to restaurants and some regular customers. One of Williams’ dreams is to have a farm stand at the Brewster Road location, where he can sell produce and eggs from his 250 chickens. He’s working on a plan for a CSA-like “greens share.”
He’s also open for school tours, noting, “The kids love it.”
Williams and his son also want to help homeowners learn the basics of installing small aquaponics systems at their homes. There are kits out there, some good, some not so good, according to Williams, and he and Gavin are happy to share their expertise. “We may be offering classes soon,” he said, adding that the main concern for home systems is keeping the Ph balanced. “Keeping it at 6.5 is a good balance, it’s what the fish need and what the plants need,” he said.
While New Hampshire has warmed to the idea of aquaponics, there have been personal challenges, Williams said. In the winter of 2015, Winter storm Juno collapsed his roof, and he and Gavin rebuilt the building themselves. “We were out of commission for a year,” Williams said. But they believed in their idea, and gradually reopened.
He sees a future for aquaponics in New Hampshire, noting that people are more interested in locally grown food.
And for now though they have no formal store as yet, he said, “If someone comes in and wants a lettuce, we’ll sell them a lettuce.”
Victory Aquaponics is located at 17 Brewster Road in Londonderry. For more information, call 781-974-0908.