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Exploring Iowa Aquaponics with Early Morning Harvest

It's still dark as I crawl into my ice-cold vehicle on the morning of November 19th. I am on my way to Early Morning Harvest’s fall event. By the time I pull into the drive I am hours away from home and the sun spills over the hilly landscape. The first person I meet is Earl who shows me where to go. I am meeting Amos, the Livestock Education Coordinator from Practical Farmers of Iowa, at the event to do some tabling for PFI.

Earl Hafner wears his hat cocked a bit

to the side. He walks Amos and I through the mill, it's clean and bright white with small bottles on a stainless-steel table. The first bottle in each row is a whole grain, one full of wheat berries, another rye, buckwheat, and corn. The bottle adjacent to the whole grain is its corresponding flour milled in that very room. Earl describes the flat stones that grind the grain and the heat this process produces which causes condensation, a pesky problem that, with creative problem-solving Earl has managed to mitigate. Among other things, he uses a clothes dryer vent over his sifter to keep the material cool. It seems the theme on this farm is creative innovation, a skill Earl has passed onto his son, Jeff Hafner.

“Milling was Earl’s hobby and aquaponics was my hobby and now they are both part of the business,” Jeff kiddingly says “We aren’t allowed to have any more hobbies.” Jeff’s Aquaponic farm is like nothing I’ve seen before. To a non-farmer’s eye, it looks like the kinds of growing spaces you might see in a Star Trek episode. The greenhouse is filled with noises of bubbling water and pumps, greens are nestled into Styrofoam puzzle pieces that float in beds of constantly moving water. There are tubes everywhere: on the ground, coming down from above head, waist height, arching over the plant beds.

I got an exclusive tour of the Aquaponic farm from Amanda Kanehl, an Early Morning Harvest employee and friend of the family. She has just started working in the green house where the aquaponic farm lives. She says “I love my job” in a way that makes me actually believe it. Amanda wears heavy boots that thud against the wooden path as we walk. She indulges all my curiosities. She catches a fish to show me their size and color. It's bigger than I expect and manages to break free of her grasp. As I panic, she calmly grabs the thing and plops him back in the water. The vibrant chard catches my eye and I gush over its color. She lifts the rainbow chard so I can see the beautiful colors also present in the root systems, they look like wet hair. This little plant has a punk rock pink shag that is doing more than you might guess.

The North Central Regional Aquaculture Center describes Aquaponics as “an integrated production operation that encompasses recirculating aquaculture systems and hydroponics to produce fish and plants in a closed-loop system that mimics the ecology of nature. Simply said, the fish produce nutrient-rich effluent that fertilizes the plants, and the plants filter the water for the fish.” (Pattillo, 2017)

Before me stands four 300-gallon tanks housing in the ballpark of 125 tilapia fish. PVC pipe connects these tanks to a four barreled filtration system meant to catch solid waste. “If solids are not removed, bacteria will break down the feed causing an oxygen deficit that can kill the fish and beneficial bacteria in the biofilter. It can also cause a release of ammonia, which is directly toxic to the fish,” (Pattillo, 2017). Don’t forget that the water, after it travels through the plant beds, returns to the fish tanks. Too much nitrate, too high pH, too much oxygen, and/or not enough oxygen can all lead to poor crop and dead fish.

Early Morning Harvest uses two types of plant beds: flooding beds and nutrient film technique beds (NFT). The flooding beds are filled with small pebbles suitable for direct planting. Every so often these beds are flooded with water then drained in order to bring nutrients to the plant’s roots. The NFT beds have water constantly running through them. In this system plants are nestled into foam floating on the surface of water or placed on top of a metal grow tray that submerges the roots in water while supporting the plant upright. Once water has passed through the root systems it is all funneled to the affectionately named ‘hot tub’. The ‘hot tub’ is a massive in ground sump tank that is aerated via large air bubbles making their way upward from the deep (hence the name hot tub).

Amanda lifts one of the foam islands floating in the NFT bed and reaches into the water searching. Her hand surfaces with a small square attached to a hose, she puts it into my hand. As I close my fingers around the square stone like object, I can hear and feel pressurized air emitting from the thing. “This is an aerator,” she says. “The process of aeration agitates the water, creating a large surface area for contact between air and water, thus enhancing gas exchange. The smaller the bubbles, the greater gas exchange that can occur. Aeration should be provided in the culture tank to aid the removal of carbon dioxide (CO2) and increase the dissolved oxygen (DO) concentration.”

Water is then piped from the hot tub back to the fish. The tilapia were sterilized prior to purchase, but a couple of the fish found a way to spawn. As the great Jeff Goldbloom says in the classic thriller Jurassic Park “life finds a way.” Amanda told me about the mishap. The baby fish were able to break free of the tank and make their way, via the PVC pipe waterways, into some of the vegetable beds. The fish, if left in the bed, snack on the roots and degrade the crop among other issues. They’ve designed a system to remove the fish from the beds. “We remove all of the plants and one person has to stand in the bed while two others hold a net at each side,” Amanda explained. “The person in the bed kicks along with the net to capture as many rogue fish as possible.” A process that sounds both innovative and entertaining.

My main takeaway from visiting Early Morning Harvest is that innovation is a process. It’s a creative, liquid, and sometimes slow growing root that finds its way to the good stuff in its own time. Innovation, like the water cycling through the aquaponic farm, requires constant movement and the embrace of change. I suspect Jeff and Earl have their sights fixed on the future of farming in Iowa. I suspect this, not only because they’ve created a closed loop sustainable way to produce food for their community, but because they’ve created a legacy of learning for those they employ.

Jeff met Amanda long before she worked for him. He purchased her a membership to Practical Farmers of Iowa (PFI) as a way to help her get started in the field. Her ambition was to become a farmer and the field days, farminars, and community of local farmers at PFI were a great way to get her started. Jeff doesn’t remember purchasing her the membership, but Amanda does. It was an act of generosity that, as Amanda undoubtedly rises to a leadership position in her field, will likely pass onto others. If I were Jeff and Earl, that is the legacy that would make me most proud. A legacy of learning, embracing change, and feeding others in more ways than one.


Pattillo, A. (2017, October). An Overview of Aquaponic Systems: Aquaculture Components. North Central Regional Aquaculture Center; Technical Bulletin Series: October 2017.

Early Morning Harvest. (2022). Retrieved From


About the Author

Rachel Burke is an artist, farm enthusiast, and sustainability nut. She is currently serving a term as a Land and Water Steward for Green Iowa AmeriCorps at Practical Farmers of Iowa. Rachel recently moved to rural Iowa with her husband and cat. Together, they dream of having their own little creative farmstead.


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