by BRITTNEY MARTIN
For Reporting Texas
A visitor could get lost in Rob Nash’s greenhouse. Swiss chard and tomato plants create a maze. The smell of basil is overwhelming, and the leaves are as big as a human hand. All this teeming life is growing in the waste that is filtered and vacuumed out of an aquarium through a newly flourishing agricultural method known as aquaponics.
Aquaponics is a word and practice created by combining “aquaculture,” or raising fish, and “hydroponics,” the use of recirculating water to grow crops. While aquaponics research surfaced in the late 1960s, commercial aquaponics didn’t take off until the last decade.
In a world where consumers pay more attention to sustainable farming, the slow food movement and organic cultivation techniques, aquaponics is taking off. The University of the Virgin Islands has trained 600 people in commercial aquaponics since 1999 and will train up to 80 more in 2013. The Aquaponics Association of North America has more 400 voluntary members.
But the field of aquaponics has no specific definitions or parameters. Beneath the surface of the movement, people who are farming on a commercial level have already divided into groups with different belief systems and financial goals. In Texas alone, there are find purists, innovators, and people who want to save the world.
Adam Harwood lives and works on two acres of land in San Marcos. What sets him apart is his system. A self-proclaimed “purist,” he traveled to the Virgin Islands to take a weeklong aquaponics workshop put on by the University of the Virgin Islands and ended up staying for months. When he returned, he bought his property and began recreating the UVI commercial system from memory. Now, 36 months later, Harwood has built three complete aquaponic systems and sells hundreds of pounds of produce and fresh tilapia every week.
Harwood was reluctant to specify how much he spent on his three systems, but said they cost between $35,000 and $50,000 to set up. He has the potential to grow 5,400 plants per month and sells them for $4 each. He harvests no more than 250 fish per week and sells them for $3 each.
Harwood swears by the UVI system. In each of his greenhouses, he has two tanks holding roughly 1,000 tilapia each. The water from those tanks is pumped into the first of three filtration systems. It collects solid waste in a cone at the base of the tank, and gravity moves the waste from that cone to a spout on the outside of the greenhouse. Harwood collects the waste and sells it as fertilizer. The water then cycles through an additional two filtration tanks where bacteria transform the wastewater into a suitable nutrient source for plants.
“Fish excrete their extra nitrogen off of their gills in the form of ammonia,” said Donald Bailey, an aquaponics research specialist at UVI. “There’s nitrifying bacteria on all the surface areas, and they take the ammonia and convert it through their processes into nitrates, and that’s a form that plants prefer.”
The wastewater then moves through a degassing tank to remove harmful gases like methane and carbon dioxide. The water then flows into two deep-water rafts each holding eight rows of floating crops.
The roots are emerged at all times and take in all the nutrients they need to grow from the constantly flowing wastewater. This process not only provides a fertilizer-free, all-natural crop, but also filters the water enough to go back into the fish tanks.
This mutually beneficial system continues constantly and produces two organic end products: fresh tilapia and fruits and vegetables. Harwood sells all of his produce and fish himself at farmers markets and community-supported agriculture (CSA) systems.
“When I deliver my food to the end user it has very little transportation against it, and it’s still connected to its root structure, which makes it like no other conventional food you buy with the exception of buying a live chicken,” Harwood said.
For many years, the broken link in aquaponics farming has been the fish feed. Organic feed can be hard to access and expensive for use on a large farm. To combat this, Harwood set out to help develop an organic fish feed, which he now uses to ensure that the entire system is completely organic.
Harwood says he owes his success to the UVI system and believes any deviation from it cannot be considered aquaponic farming.
“I’m not looking to make any innovations. What I have here works, and it works for a reason,” he said.
Rob Nash of HannaLeigh Farm in Austin takes a different approach. He developed his hybrid technique five years ago through a great deal of research, collaboration and experimentation. When he’s not working in the greenhouse or spending time with his family, he’s on online forums or meeting up with others to share ideas about aquaponics.
“Aquaponics, I would say, has been one of the most open-source forms of agriculture that’s ever happened because it’s so relatively new, especially on a commercial level, that there’s more people collaborating and exchanging information and ideas,” he said.
Nash combines deep-water raft culture with what’s called the media technique, which, unlike Harwood’s chamber-based technique, uses gravel to filter the water. Like Harwood, he has two tilapia tanks in each greenhouse and a small pump to move water through the system. Instead of going through a series of filters and degassing chambers, however, the water flows directly into several raised garden beds filled with a media made up of granite and river rocks.
As the water moves through the gravel-like combination, the fish waste is filtered out and then consumed by red wriggler worms living in the garden beds. It’s actually the worm waste that acts as a natural fertilizer for the crops in the garden beds. The filtered water then flows into deep-water rafts, where more plants are growing, as in Harwood’s system. Finally, the water is returned, clean and filtered, to the fish tanks.
Aquaponic farmers can raise blue, Nile and Mozambique tilapia on their private facilities if they get a series of permits. First they have to get an aquaculture license from the Texas Department of Agriculture, then a wastewater discharge permit from the Texas Commission on Environmental Quality that ensures there’s no wastewater runoff from their farms. Lastly, farmers need an exotic species permit from the Texas Parks and Wildlife Department. All species of tilapia are technically prohibited in Texas; however, these three can be used in aquaculture with the proper permits. In some counties, a license is required to sell fish fish to the public.
Nash’s entire operation uses about 400 gallons of water a week. He only has to replace the water that evaporates or is taken up by the crops. This system requires significantly less water than traditional farming or hydroponic systems, which leave farmers with wastewater at the end of each cycle that has to be completely replaced and replenished with nutrients.
While Harwood would call this hybrid method “transfarming” rather than true aquaponics, experts say that’s not the case.
“Combining aquaculture with hydroponics is really the main criteria for aquaponics, and the actual system design is different for different groups promoting different things,” Bailey said. “Our original system was a media-based system back in the early 1980s, but they just were impractical to use for the large scale that we were going for.”
Michael Masser, the head of Texas A&M University’s Wildlife and Fisheries Sciences department, says no research has been done on the economic viability of commercial aquaponics in Texas.
“I would consider my farm profitable, but it’s not paying any payroll, so it’s technically a break-even hobby farm at this point,” Nash said. “I would need to be at least twice the size as I am for it to ever be able to pay the bills.”
Nash says that if he were that size he could make $1,000 take-home pay each week after accounting for the farm’s weekly maintenance cost of about $500.
“I personally would like to bring home at least $50,000 or I feel like I’m missing out on a different job opportunity, and my goal is to be there by spring,” he said.
In the meantime, Nash sells his vegetables at the weekly farmers’ market in Lakeway and to the restaurants Tony C’s and Mandola’s Italian Market in Bee Caves. As his farm grows, Nash thinks he will have to narrow his focus to just one market to keep up with the demand and maintenance. While he enjoys the intimacy of farmers’ markets, he thinks the routine culture of restaurant supply will allow him to spend more time with his family.
Nash also services two different markets by selling tilapia fingerlings to aquaponic system-starters and giving lessons to both backyard aquaponic gardeners and commercial farmers.
“I’d say most of the people who get into aquaponics enjoy the tinkering aspect of it because you get to put something together and watch it grow,” Nash said. “Anyone who has ever attempted and/or failed at gardening can appreciate the growth that you get out of these systems and is usually real excited about doing it for themselves.”
Aquaponics and Earth Sustainable Living is a nonprofit organization based in DeSoto, just south of Dallas, that uses aquaponics to aid people in need all over the world. John and Teresa Musser began building what they call their “cycle of life micro-farm” in their backyard three years ago.
Their farm sits on an eighth of an acre of land and houses several chickens, goats and rabbits along with their media-based aquaponic systems.
Their mission is to go into parts of the world where people are hungry and teach them to emulate their cycle-of-life system. They have developed a container with a pump that runs on 33 watts of power. Fish go in the bottom of the container, and a gravel grow-bed sits on top. The system produces vegetables from the grow bed and uses a portion of the water to create the fertilizer.
“We tell people it’s not going to grow enough fish for a whole tribe of people, but the fertilizer that you can get from it can feed an entire village,” John Musser said.
The Mussers divert about 10 percent of the water from their aquaponic systems into underground tanks. They then gather together the shredded paper from their office, the contents of their chicken, goat and rabbit enclosures, old plants, leaves and other trash and put it in a compost heap. Using the stored wastewater, they drench the compost two times, which speeds up decomposition. After that, they add molasses, and within three days, thousands of worms are breaking everything down.
“We can make certain types of fertilizer and mulch in 14 days, which is unheard of,” Musser said. “We teach people how to make a fertilizer factory.”
The Mussers say they spend from $500 to $700 on plants and peat moss each year; everything else they use is recycled. Domestically, many of the vegetables and fish are made into soups or canned individually and sold to volunteers and people taking canning classes from the Mussers.
The Mussers have set up cycle of life micro-farms in Mexico, Belize and Haiti. All the money they raise in combination with donations goes toward their outreach projects and paying a full- and part-time staff of eight.
“When we go into other countries, we’re thinking about what they have in that habitat, and that’s the challenge because you can’t just take what we have in our backyard here in Texas and go to the rain forest in Belize and replicate that exactly,” Musser said. “We have to figure out what natural resources they have and use those to recreate our system.”
BRITTNEY MARTIN writes for Reporting Texas, a UT School of Journalism program, where this story was originally published. It is reprinted here through a news partnership between Reporting Texas and the San Marcos Mercury.Email | Print