Fish food: Aquaponics offers full-circle farming

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Fish food: Aquaponics offers full-circle farming

out fr Tucked away along a squirrely offshoot of Jonathan Creek Road, Dennis “Bear” Forsythe’s 15-by-15-foot greenhouse is like his own private Eden. The small outbuilding in rural Haywood County holds 500 plants representing 58 species, everything from pineapple to pepper.

“I just love doing it,” Forsythe said. “You have running water and it’s soothing, it’s relaxing. You come out here and you say, ‘I grew everything here from seed.’”

The running water is a bit of an anomaly compared to most greenhouses. So is the complete absence of any soil. Instead of soil, the plants get their nutrients from the fish swimming in two separate fish tanks inside the building. Specifically, from their waste. It’s a method of agriculture that’s been gaining traction over the last decade or so, a method known as aquaponics.

“Everything you see gets watered with fish water,” Forsythe says, panning the array of sprouting plants, ripening fruits and sprawling vines filling the building.

The idea is relatively simple: to grow, plants need water and nutrients, especially nitrates. Fish also grow in water, and their waste is quite nutrient-rich. An aquaponic system circulates water from the fish tanks, through all the various gravel-filled pipes and pots that house the plants, and then back to the fish.

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This kind of agriculture uses less water than conventional gardening, because no water is lost through absorption to the soil and the roof and walls mean that little is lost to evaporation. There’s some further environmental benefit too, because you’re raising protein along with plants, and the waste produced by that protein can go right back into plant growth, eliminating the need for environmentally expensive produced fertilizers.

In practice, though, it’s not quite that simple.

“Aquaponics is a never-ending learning process,” Forsythe said, “because you’re constantly adding new things to see if it grows.”

Forsythe, a farm-boy-turned-recreational-gardener, spent a good two years studying aquaponics before he bought so much as one piece of PVC pipe. The retired hotel remodeler has about $5,000 invested in the building he constructed, and his research still isn’t done. He’s always watching videos, chatting online with other aquaponic growers from around the world. He’s always tinkering with the system, with the nutrient balance, with the types of plants he grows.

“An aquaponic system, in order for it to start producing, it takes six to 10 months to mature,” Forsythe said.

Rolling in tomatoes

When I visited Forsythe’s home in July, the system was just on the cusp of maturation. The bacteria, pH and nitrates were just beginning to work together, just beginning to hit the sweet spot necessary to sustain the verdant explosion erupting inside the greenhouse. Tomato vines grew rampant, but Forsythe himself had only had two or three cherry tomatoes to eat so far — his granddaughter took care of the rest. Squash flowers were blooming and vines lengthening, but no fruit had yet resulted. Kohlrabi and peppers were still in the future.

One month later, all that’s changed. The Forsythe family is rolling in the tomatoes, 15 of them sitting uneaten in the kitchen and a whole lot more ripening on the vine when the phone rang with a call from the Smoky Mountain News. He’s getting ready to eat his first cantaloupe, and the peppers and lemon cucumbers are coming along. The corn is 2 feet tall, and the tilapia just had babies.

“Right now everything’s just growing all over,” he said.

The family isn’t having any trouble keeping up, though, the farmer noted. Between Forsythe, his wife Donna and their children’s families who live along the same road, there’s plenty of appetite for fresh fruits and vegetables.

Go it yourself

When it comes to food, Forsythe’s philosophy is along the lines of “if you want something done right, you gotta do it yourself.”

“If you want good food, you want it organic, the only way that you know you’re going to get good, healthy food is to grow it yourself,” he said.

From start to finish, Forsythe knows where his food is coming from. He plants the seeds, feeds the fish, grows the duckweed with which to feed the fish, prunes the plants, harvests the fruits. Soon, he’s expecting to start harvesting the additional tilapia, as well. He could have started doing so already, but he got himself into a bit of a pickle.

“They’re supposed to be here for when you want a fish, come out and fillet one of them, but I’ve named every one so that’s not going to happen,” Forsythe said, pointing out 14-inch Big Jack.

Seeking biosecurity

With rain barrels to store water to replenish the system — the water’s never changed, just added to as the plants absorb it — Forsythe figures he could pretty much sustain four people off of the system without having to depend on any external food or water sources.

That’s an attraction that’s had more and more people trying their hand at aquaponics over the last five years or so, said Debra Sloan, an aquaculture consultant for the N.C. Department of Agriculture who is based in Franklin.

“I think it’s certainly something people show interest in because you’re growing plants in a controlled environment and you’re growing fish in a controlled environment,” Sloan said. “That’s biosecurity.”

Biosecurity here meaning assurance that food sources stay free of contamination, infection and disease.

Meanwhile, the aquaponic setup uses about one-tenth the water of conventional agriculture, uses less space and produces fresh fruits and vegetables year-round, providing it’s heated in the winter.

“I’m trying to get everything situated to where if I didn’t want to go to the store, I wouldn’t have to worry about the store,” Forsythe said.

That’s probably another thing that’s attracting more and more people to try out aquaponics, Sloan said — the independence it offers.

“I’ve seen more interest in aquaponics the last, say, five years than in my entire 30-year career,” she said.

Part of the solution?

With the world population on the rise and local foods now a hot commodity, more people may be thinking about aquaponics as a way to live sustainably, more closely on target to an environmental budget, Sloan said. That’s certainly part of why Forsythe’s doing what he is.

“I honestly believe if you’re going to have enough food, people’s going to have to start doing this,” Forsythe said.

It’s possible that aquaponics could be a big part of the solution to feeding a growing world, Sloan said. Because aquaponic growing can be done on a smaller land footprint, because it uses less water, because the plants can grow year-round — it has a lot going for it.

But it’s too early in the game to reach conclusions.

“I think that the jury’s still out on that, but I think that’s a real possibility,” she said. “But I don’t know. It all depends on if we can get these systems to a size that is economically viable.”

If conventional farming is expensive, then large-scale aquaponic farming is astronomical. There’s a lot more infrastructure. Glass panels, piping, pumps, heating for the winter … it all adds up. And it hasn’t been much tried on a large commercial scale.

“Nationally, we really don’t have, to my knowledge, a good model to see the scale to make it commercially viable,” Sloan said. “It costs a lot of money to invest if you’re going to go into a real aquaponic system.”

Not full-blown rosy yet

Of course, small-scale aquaponic growers — people like Forsythe, who run small systems with enough food to feed a family and maybe sell at a farmers market or donate to a food pantry — are becoming more and more numerous.

But there still aren’t a lot. Sloan guesstimates no more than “maybe a handful, two handfuls” scattered throughout the region. Forsythe would like to see those handfuls multiply.

“What would happen if, say, two billion people, three billion people, started growing their own food?” Forsythe asked.

Sloan isn’t particularly certain that a collection of small-scale systems are the solution, however, for the simple reason that aquaponic growing is tricky.

“You’re trying to learn how to raise an animal and plant concurrently, and that’s hard,” she said. Usually when she talks to someone who’s interested in setting up an aquaponic system, she encourages them to try hydroponics — growing plants without soil — first.

“The whole ‘let’s grow our food, back to nature thing,’ that’s a feel-good thing,” Sloan said. “You have to be good at it.”

Not everybody is, she said, which is why it’ll be important to see how it goes as the project of a large-scale investor before promoting aquaponics as the way of the future for food. It’s not time to paint the picture as full-blown rosy, because “I don’t think we have enough information for it to be that rosy.”

Maybe the jury’s out on whether aquaponics is the solution to all the earth’s eating-related woes, but Forsythe’s feeling pretty rosy about his system as a solution for both his diet and his sanity. Stress and anger dissipate when he plants seeds against the background noise of trickling water and the erupting garden offers a flavorful snack whenever he’s in the mood. With a nonstop harvest now coming in, the family won’t lack for food that’s as fresh, organic, local and inexpensive as it gets — even when winter descends on the Smokies.

“This is just something I love doing,” he said.

What’s in a word?

“Aquaponics” is a mash-up of “aquaculture” and “hydroponics.” The former is a fancy word for fish farming, while the latter means growing plants without soil. Hydroponics means growing plants with recirculating water fertilized by fish raised on the same location — but without soil.

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