The catalyst for the move to aquaponics occurred several years ago when, according to Tim Goodenough, “input prices were high, grain prices were fluctuating constantly and Mother Nature was throwing us curve balls.”

As a result, Tim started researching different agricultural methods; he had fish farming in the back of his mind after seeing such an operation on an American Soybean Association trip to South America several years earlier.

“When I came back home I had a lot of information about fish farming and we began looking into the concept,” said Tim, who was raised on the farm and runs it with his wife, Bonny, and their four children. The family’s research led them to consider aquaponics.

Aquaponics combines aquaculture, or fish farming, and hydroponics (raising plants without soil), in a closed-loop system. The nutrient-rich water that results from raising fish provides a source of natural fertilizer for the growing plants.

Ready to give the aquaponics operation a go, in 2014, Tim and Bonny purchased a used four-section, 13,600-square foot greenhouse in Eau Claire, Wisconsin The structure was still standing so the family spent three months physically disassembling and dismantling it before transporting it piece by piece to their farm.

The next year, the family finalized construction plans for the greenhouse and the attached lean-to building that would house the mechanical systems. Concrete piers were poured and support posts and trusses were set.

The re-construction of the greenhouse began in 2016. The Goodenough’s worked in tandem with a construction crew for six months until the facility was completed. They also hired Ron Hammes Refrigeration, a residential and commercial HVAC company based in La Crosse, Wisconsin, to handle installation of the heating equipment and piping.

TESTING THE WATERS WITH ADVANCED ENVIRONMENTAL CONTROLS

With the 13,000 square-foot greenhouse ready for operation in November, and the wintry Wisconsin weather setting in, the heating system needed to be installed quickly.

“We required air temperatures of about 70 degrees in the greenhouse year-round and water temperatures between 70 to 75 degrees for the fish and plants to thrive,” said Bonny.

Another important concern: The greenhouse structure, which consists of lightweight polycarbonate, could collapse under the weight of a heavy snowfall. 

“Snow could wreak havoc on our structure and so it was imperative to get the heating system online as soon as possible,” Tim added.

To meet project parameters, James Hammes, president of Ron Hammes Refrigeration, recommended the installation of four 399 MBH Weil-McLain Evergreen boilers with primary-secondary pumping in a Multiple Boiler System (MBS). In this configuration, a master boiler controls the modulation and sequencing of boilers on the network to achieve the desired system supply temperature.

“With the automatic sequencing feature, the boilers communicate directly with one another so they sequence themselves and rotate as needed,” said Hammes. “They operate to optimize energy use and efficiencies. When heat is required, the boilers will stage on one-by-one as needed.”

The Evergreen units were tied to existing heat exchangers on site and installed as part of a Wadsworth system, a building control solution that monitors external temperature, wind speed and direction, precipitation and humidity, and also internal factors such as temperature and humidity.

To maintain conditions, the advanced Wadsworth system cycles the boilers, heat exchangers and grow lights on and off, and opens and closes vents and shade cloth based on the amount of sunlight from the sun. It is designed to keep humidity and temperature levels inside the grow operation at targeted parameters.

“We are essentially trying to create the longest summer day of the season year round in the greenhouse,” said Tim. “The vents, lights and shade cloth are all computerized and move automatically to maintain conditions.”

With the heating system in place, the nursery was filled in early December with 130 tilapia and several varieties of vegetables.  When all tanks are filled, they will hold approximately 2300 fish.

RESULTS HOLD WATER

According to Tim, the installation of the Weil-McLain boilers went smoothly, and the family’s Floating Gardens LLC aquaponics farm operation is already a success.

The four Evergreen boilers maintain proper temperatures in the building, while providing supplemental heat for the fish tanks and nurseries.

“The boilers are very energy efficient and will cycle on and off as needed,” said Tim. “They typically shut off when the temperature outside is 65 degrees and higher.”

Alleviating a major concern, the boilers also allowed the greenhouse to stay snow free all winter.

“We had some major snowfalls this last season, but it always melted and never accumulated on the roof of the greenhouse,” said Tim.

Today, the Goodenoughs are producing approximately 250 heads of lettuce a day with varieties of romaine, butterhead and summer crisp. The family also is growing other produce such as swiss chard, peapods, string beans, kale, tomatoes and radishes.

“We harvested our first gourmet lettuce crop in April, and we will begin selling freshly harvested tilapia mid-year, when the fish have reached market weight of about 1½ pounds,” said Bonny.

The Goodenoughs sell their products at their on-site market, and to farmers markets, local restaurants, schools and grocery stores.  

“We believe aquaponics is the new face of farming as it is sustainable, healthier and can supply more food per acre than traditional methods,” said Tim. “We are very happy with the system we have in place, and the Weil-McLain boilers are a key component in making this efficient growing method a success.”

Publication date: 11/20/2017

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