© by David Yarrow, December 1997
|"Problems can be turned into opportunities
to develop solutions.
Necessity makes us do
what reason will not."
Quote of the Day
In southern Missouri, in the heart of the beautiful Ozarks, a quiet revolution in biotechnology is incubating. Four miles north of the Arkansas border, S&S Aqua Farm is a family farm near West Plains, Missouri. In the last decade, Tom and Paula Spereano developed a unique, innovative, low-cost food growing system in their solar greenhouse.
The S&S Aqua Farm brochure allures with idyllic imagery:
|"Imagine gardening year-round, with no weeds to pull, no bending to plant or harvest, no worries about watering or weather. Picture you in mid-winter working in a green, vital, healthy environment—doing what you love to do."|
Tom and Paula's growing system is called Bioponics—from Greek "bios," meaning "life, or mode of life." Their hybrid system integrates aquaculture and hydroponics in a simple—and simple to operate—way to produce premium fish, fresh vegetables, herbs, and other plants. This is no mere hobby, theory or novelty, but a steady, reliable, no nonsense source of family food and income.
They explain, "You feed the fish; the fish feed the plants. Plants help the fish by filtering fish wastes from the water. You harvest the vegetables and fish. The more natural we make it, the better it works."
In their closed cycle, self balancing system, mineral salts as plant food are replaced by natural nutrients from a biological source: fish effluent. This practical, ingenious system needs no expensive equipment or patented parts, and uses easily available materials to grow safe, chemical-free, superior quality food. And is adaptable enough to provide family food supply, or expand to commercial scale.
The heart of Bioponics is the fish tank. Tom uses standard polyurethane hatchery tanks available from PolyTank, Inc. and commercial suppliers. A tank can be larger or smaller, to comfortably house any number of fish or fit any space.
Tom's tanks are stocked with Tilapia, the world's most popular fish for aquaculture, a hardy, disease resistant, warm-water fish native to Africa and Middle East, and raised for food by ancient Egyptians. They're delicious, with white flesh and few bones. Tilapia tolerate low oxygen and poor water conditions that will kill most fish.
Tilapia are vegetation eaters. They devour algae in addition to their regular feed. Any excess plant cuttings tossed in the tank, they feast on happily. Cuttings are broken down by bacteria into algae, then fish filter the algae out. Their gill rakers take out anything over 3 microns, which is red blood cell size.
"This helps keep water really clear," explained Tom. "With our system, we never have cloudy water. You can see a dime on our tank bottoms. When we harvest beds, we rake the gravel. Any algae drains into the water, and fish filter that out, too, so they get everything back. Extremely simple, but very efficient."
In a production system, maximum growth is achieved by assuring high protein intake, so Tom's fish are fed a daily ration.
"What do you feed the fish?" I inquired.
"5106 Purina 40% protein Trout Chow," Tom replied, "the most chemical-free I can find. It doesn't have copper sulfate, tetracycline, actinomyecin, and additives, like many commercial fish foods do. I had no idea the quantity and number of antibiotics and chemicals is so high. A label reads like a chemistry set index."
The feed conversion rate for Tilapia is excellent: a pound of feed yields a pound of fish. Tilapia grow fast—to over one pound in 9-18 months—to provide firm, white boneless fillets (40% by weight), readily marketable at 3/4 pound. Tom sells fish over one pound live weight—generally 1.5 pounds. Fish are harvested regularly by size using nets that only catch larger fish.
Animals excrete wastes. Fish dump excess nitrogen (urea, nitrite, ammonia) and other wastes into water. Crowding fish together in a closed container, and feeding them high protein diet to force rapid growth, generates a lot of wastes. If these fish metabolites aren't removed from the water, they will quickly build up and poison the fish.
Toxic waste—a key limiting factor in aquaculture—restricts a system's production capacity. So fish farmers invest a lot of money, time and technology in waste disposal problems. Pumps, filters aerators, sedimentation tanks, and more equipment clutter and confound most fish farms.
In Bioponics, fish wastes become plant food, and expensive machinery and complex technology are replaced by biology. Plants grown in beds use nutrients in fish water, and purify the water to benefit the fish. A Bioponic system is simple and revolutionary for the very reason it doesn't use technology normally necessary for aquaculture and hydroponics.
Plants grow in permanent beds which contain pea gravel as growing media. Periodically, pumps flush these beds with water from a fish tank. Plants get all the nutrients they need from this irrigation water with no cost or fuss to mix chemicals. Thus, animal wastes become plant food, and Bioponics removes the need to add fertilizers to water to feed plants.
Beds can be any size or construction, from wood-frame home built boxes to standard commercial polyurethane containers. S&S Aqua Farm has 2400 square feet under solar greenhouses. The growing system is segmented into "nodes," where a node is one fish tank with six growing beds. The beds are under glazing and fish tanks under standard roof. The black fish tanks absorb sun through winter, but are shaded in summer.
Fish water—effluent—is pumped from a tank through 1-inch PVC pipe straight to growing beds to trickle through their length, then pumped back to the tank. Effluent isn't filtered or purified before reaching growing beds. Water is aerated as it flows out holes in the pipe and trickles over gravel.
"It's been suggested if I use the right size apertures, I can increase the aeration of the water" Tom revealed. "But my dissolved oxygen levels are high enough right now—6.5 or so—that I've got all the dissolved oxygen I need."
In the stable, moist greenhouse atmosphere, plants grow in denser spacings than conventional garden beds. Tom's beds are so nutrient-rich and fertile, plants grow in less time than by conventional methods—and larger, too. Tomatoes are tied up in tall vines, and peppers become baby bushes. And cuttings from almost any plant (even trees) will root and grow if stuck in a bed, with NO rooting hormones or chemicals.
In return for fish effluent feedings, plants—through their roots—purify and recharge the water for fish. In a bonus, when a bed is harvested, the gravel is raked, and any algae washes into the tank of hungry tilapia.
"Experience with hydroponics," explained Tom, "was there's always a toxic residue left: salts. Modern commercial farming faces this same toxic dilemma: the residue from fertilizer is salt."
Conventional hydroponics purify water with expensive feeder lines and emitters. Bioponic growing beds are fluidized bioreactors—very efficient biofilters that purify water by biological methods and commonplace materials, without separators and clarifiers to remove solids.
The Bioponic approach to system integration not only knocks out nitrogen troubles, but carbon dioxide, too. Plants need CO2 to grow. In winter, this scarce gas is a growth limiting resource.
"Everybody said, 'put in CO2 generators.' But I've got tanks full of CO2 generators. They're alive and have fins. Fish are CO2 generators for the system—something I didn't foresee, just a natural side effect. That's a lot simpler than hydroponics."
In nearly a decade, Tom and Paula have experimented with growing many different plants—ornamentals, herbs and vegetables—from seed, seedlings and cuttings. Most attempts were successful. They've grown food crops, fresh-cut herbs, house plants, and rooted cuttings. They also supply starts for flowering basket sales.
"We grow over 450 different varieties 12 months a year in a commercial production system," Tom revealed. "Lots of leaf lettuces, not head lettuce, three types of eggplant, over a dozen tomato varieties, and more than 20 herbs. And peppers, sweet and hot, over 41 varieties." Tom slowly detailed each variety with the familiar ease of a veteran tour guide and salesman.
"We also grow over 20 flowering and ornamental plants," he went on, "plus potted plants, hanging baskets and cut flowers. In spring, we have all the normal garden starts: peppers, tomatoes, cukes, brassicas..... And herb planters."
Additionally, they produce value-added specialty products. "Currently," Tom said, "we bottle about nine peppers as hot sauces under the 'Ozark Originals' label. And $6 per pound for lettuce mix when people won't pay $2 per pound in the store. Keeps for a week, but store stuff won't, even if refrigerated."
S&S Aqua Farm wholesales to two local restaurants that pay premiums for the farm's fresh, flavorful produce, salad mix, hot sauces, and fish. They also retail to subscribers, and sell excess at a local Farmers Market, of which Paula is currently President. Also, I got the impression Tom sells a good amount to a steady stream of visitors who come to see this food growing revolution.
To sustain this self-contained, polycarbonate enclosed, mini-ecosystem of plants and animals in healthy balance and productivity, many complex, synergistic interactions occur in this low tech setting Tom has grown fish and vegetables enough in nine years, and studied enough scientific literature, to know plants alone do not purify the water for fish. Plant roots can't absorb ammonia, urea, nitrite, and other animal wastes.
Tom's closed cycle ecosystem has a third, invisible living component: bacteria.
"I've raised fish for 43 years—since I was seven. We understood from the very beginning that bacteria are vital to fish health by reducing ammonia and nitrites," Tom said. "With a microscope and staining technique, you can see these microbes. Otherwise, they're too small and transparent to be visible."
Unseen, unseeable, a few pounds of micro-organisms thrive on gravel in the beds. Plant roots only take up nutrients after the microbes consume and convert them. It is these teeming tiny creatures that filter, convert fish wastes to plant food and recharge the water.
"We have fairly high pH," Tom explained, "so nutrients can't cross the pH barrier. Extension Service said add sulfuric acid or cider vinegar to reduce pH to 5.4. It took me three years to figure out why it works, when it shouldn't—that bacteria carry nutrients against the pH barrier. That insight came from several magazine articles and a book from Britain."
"Growing beds aren't just gravel-filled trenches, but fluidized bioreactors—living biofilters," Tom enthused. "In a mechanical filtration system, this key component must be back flushed to get solid wastes out. But with Bioponics, bacteria dissolve solid wastes, so we don't have any buildup."
Similarly, with agriculture in soil, legumes (bean, pea, vetch, clover), in their root nodules, form a symbiosis with one soil microbe (Rhizobia) that specializes in using one trace element (molybdenum) in a unique enzyme to fix the two most abundant gases (nitrogen & oxygen) into plant food (nitrate, NO3) to synthesize amino acids.
This mineral-to-microbe-to-plant, nitrogen-fixing, amino acid building food chain is a foundation to all agriculture. Legumes are a key in all crop rotation and companion planting, but the real work is done by a microbe with a trace element.
In Bioponics, similar microbial links turn animal wastes (nitrogen) into plant food (nitrates). Hidden in the gravel, billions of bacteria filter the fish water and feed the fish wastes to the root hairs of the plants.
But we really know little else about this unseen universe, and the myriad lifeforms of this microbial dimension. Yet, ample evidence indicates bacteria also synthesize many essential nutrients such as B vitamins, and primary protoplasm. For one, vitamin B12 is only made by a group of bacteria that grow in alkaline environments rich in amino acids. Many other microbes function as specialized partners in immune systems.
Who are these bacteria? What is their active biomass? How do they digest minerals into streaming liquid protoplasm? How do they digest and disarm toxins? What nutrients do they make available to plants? What other specialized functions do microbes perform? What do they require for happiness?
Population and Culture
So, in a system point of view, a Bioponic operation has three living components: fish, plants and bacteria. A healthy bacteria population is a necessity, and limits how many fish can be maintained. Without them, fish will die in their own toxins, and plants will starve. Hardware is used only to optimize the lifecycles of the three main components.
I inquired where Tom's bacteria came from. "Did you capture some wild ones by good fortune, or did you have a starter culture, like sourdough yeast?" I asked.
"Our bacterial inoculants came from my older fish tanks, which has at least 28 different organisms," Tom explained, "where commercial preparations have three. We had our culture checked for pathogenic bacteria. There are none. If other people start a new system, we send them a bottle of bacteria from our beds to jump-start their colony."
As a critical system element, bacteria must be treated with care and respect. What do bacteria need? Warmth, moisture, dark, oxygen, minerals—all present in a Bioponic system under the surface of the growing beds.
"The bacteria aren't particularly fragile. They survive temperature changes and water fluctuations quite well. But the productivity of the whole system is gaited by the health and growth rate of your bacteria," Tom insisted.
Always assure good oxygen supply: life needs this gas. Bioponics prescribes methods to aerate fish water. Cultivation of growing beds when empty provides more dissolved oxygen for fish, and increased oxygen for bacteria and plant roots.
I pointed out to Tom, even farming and forestry, until recently, gave scant appreciation or analysis to the presence and purpose of microbes in soil health and fertility. Rather, soil organisms were routinely drenched with toxic chemicals, and potting soil mixes were viewed as inert media to hold roots while nutrients were delivered as soluble chemicals.
Natural and Non-toxic
One serious threat to these Bioponic bacteria are antibiotics. Tom remembered, "We were given 200 pounds of commercial catfish feed. I fed it to our test system in the small greenhouse. Within three days, I had fish deaths. Ammonia and nitrites went off the scale. It was medicated feed, and killed the bacteria. It took the system about ten days to recover."
S&S Aqua Farm has a philosophy to guide its quest for improved biotechnology. Eating food from this closed cycle, greenhouse ecosystem, and selling it to friends and neighbors engenders a deeper responsibility for quality and purity. Tom and Paula wrote:
"Having a safe, consistent source for food is a constant concern for many people. We believe that is why we receive so many inquiries. We were truly amazed at the response until we examined our own motivation to develop the system."
"We believe in growing as naturally as possible, but our system demands it. Any pesticides sprayed on plants will find their way into the fish. Any antibiotics poured in fish tanks to treat disease will find their way to plants and kill bacteria."
"Synergistic relationships of plants, fish and microbes necessitate NO CHEMICAL PESTICIDE OR MEDICATION."
"Predatory wasps, ladybugs, lacewings, Bt and other specific organically approved methods are used to control whiteflies, aphids, and other pests and diseases of plants."
"In addition, the system is environmentally friendly. There is no effluent, no runoff, no mixing fertilizers."
Recirculation, and efficient reuse of water means only 7% per month must be replaced due to evaporation and plant uptake. Minimal electricity is used because the solar greenhouse maximizes use of sunlight and doesn't need heat. Fish tanks are black to absorb and retain heat, and water's high specific heat moderates temperature shifts. Warm water, high nutrient levels, CO2 from fish, and frequent flow allow growth all winter.
The Bioponic system is flexible. A "node"—a tank of fish and connected beds—can be small enough to fit in a kitchen. Or one or more nodes can fill a backyard greenhouse. Or a number of large nodes can function in a commercial greenhouse.
Tom's water world of well balanced animals, plants and microbes is a stable ecosystem that continually produces an abundance of food, herbs, flowers, and income. This smooth running, closed-cycle, self-sustaining system in a greenhouse is a simplified micro-model of our greater planetary biosphere. This miniature self contained universe is also very sensitive—an ideal laboratory to study biological effects of minute proportions.
Such as trace elements. This carefully controlled, steadily monitored system is an ideal environment to test the effects of the least of all the elements.
Which is what Tom did in 1997.
The results surprised him.
Testing Trace Elements
A friend of Tom's read about Planters 2—a trace element, rock powder mined by U.S. Soils in Salida, Colorado—that grew superior crops, and suggested contacting the manufacturer. For Tom's first test of rockdust in his system, he was sent 20 pounds.
"Planters 2 is supposed to be micronutrients and substances that are essential, but not necessarily available, in common soil," Tom recalled. "Like chromium. 95% of the people in the U.S. are low in chromium. We're chronically deficient in our diet, and don't have a lot in soil."
"Yes," I agreed. "I just read that exact fact in a list from the American Diabetes Association."
"For health purposes, I take trace nutrients myself," Tom continued. "We use liquified seaweed extract in our fish tanks quarterly, in case there's any missing trace nutrients. Planters 2 seemed to be a good mineral supplement, so adding trace element minerals seemed a logical extension of what we do.
"It just made good common sense," Tom admitted. "From all the literature, I expected an increase in growth, and yield. In plants and fish. So we tried it, and measured the effects. We tried to establish how much better growth was with Planters."
Beginning early in 1997, once a month Tom sprinkled four ounces of Planters 2—about a quarter cup—into gravel beds in two of his four nodes. Periodic flushes with fish water washed it in, and bacteria in the beds took it up and fed it to the plants.
This very small amount—hardly a handful—is really quite generous, since this is trace element fertilizer. The amount of chromium, cobalt, copper, selenium, vanadium, and iodine needed will fit in a thimble. Tom's system is completely closed and self contained, so any added substance stays in circulation. None is lost to leaching beyond reach of roots—unless it's harvested in the form of plants.
Precise production records in seven months of 1997 revealed 21% and 24% increases from the beds fed Planters. Before becoming a Missouri aquafarmer, Tom was a top research engineer in lasers and computer systems for Bridge Communications working at Southwest Bell. His meticulous records and calculations neither lie nor exaggerate: lettuces, tomatoes and peppers all produced significantly more in both beds fed trace element fertilizer.
Like everyone who tries rock powders, Tom sees more than bigger produce. "Plants are more robust," Tom said. "Better color. More resistant to fungus, blights, mildews, and rusts. Tomatoes flower earlier and better. We noticed, too, that plants mature faster." Tom said slowly, thinking carefully, choosing each word.
An added bonus is better flavor and keeping quality—a premium to restaurant customers. And earlier flowers improves overall efficiency, productivity and profitability.
Geology into Biology and Ecology
Tom and I discussed how a small addition to his system—a quarter cup of rock powder once a month—can cause such a jump in yield. Even in conventional systems, such a small input might generate gains of four or five percent. But nearly a quarter increase is astounding. A few pennies of powder were pumping quite a few dollars to his homestead economy.
"We are feeding the rockdust to bacteria, not directly to plants," Tom agreed confidently. "Same thing we do with wastes from the fish—ammonia and nitrites—feed it to the bacteria, who do conversion for plant uptake."
Tom has no data yet of effects on fish, but early indications are more rapid weight gain and better survival. His educated intuition suspects his fish, too, are healthier—and tastier. I pointed out this gray Colorado rockdust has been used to good effect as livestock and poultry feed. And, while breeding isn't part of Tom's production system, indications are trace elements boost fertility and reproductive vitality of plants and animals.
Tom was so convinced by seven months of data, visible signs of greater system stability and vitality, and the simple sense of it, he began feeding Planters to his other two nodes. He appreciates Planters' reputation, with a 50-year history of safe, successful use in agriculture as plant food and livestock feed supplement, and feels secure to add this rock powder to his watery universe.
I asked Tom what he believes Planters provides his plants.
"Rockdust is a composite of glacial materials, or ancient sea bed materials," Tom offered, "that contain all the micronutrients, trace elements or nutrients that may or not be available."
I explained Planters comes from a unique geological deposit that eludes classification. This odd deposit is of uncertain, controversial origin. As a mineral, it is called "Gypsiferous shale." Some think it is sediments of ancient mineral springs, perhaps similar to deposits now found at Yellowstone National Park. Which means its minerals were once dissolved in and charged by moving water. While not transformed completely to a clay, the minerals in Planters' parent rock have been partially digested from a crystalline to a biological state.
Thus, Planters dissolves more readily in water again than other types of crystalline rock, and is more quickly available for biological purposes. Whatever its geological identity, Planters has a higher solubility than other rockdusts—about 1%. In a Bioponic system, where all nutrients are water-carried, this scant 1% is a decided advantage and desirable characteristic.
I asked Tom if he has tried any other materials, such as glacial gravel dust or powdered granite, which have dense crystal structure and low solubility compared to Planters or clay.
"I read up on powdered granite," Tom replied. "You could put powdered granite in there, but I don't see what it would yield. I stay away from clays because they float on the water surface, and I'm not sure it will do the tilapia good to filter that out."
|To receive details via e-mail or snail mail, contact:
S&S Aqua Farm
8386 County Road 8820
West Plains, MO 65775
S&S Aqua Farm maintains a lively, active internet discussion list on aquaponics. Contact them to subscribe.
Other articles about S&S Aqua Farm:
Small Farm Today, June 1992
Back Home, Summer 1993
Missouri Conservationist, August 1993
The Growing Edge, Vol 5 No 2, Winter 93-4
Remineralize the Earth
Journal of Global Remineralization
Joanna Campe, Editor
152 South Street, Northampton, MA 01060
413-586-4429; 413-586-6064 fax
U.S. Soils Mining & Manufacturing, Inc.
Herb Owen, Vice President
P.O. Box 926, Salida, CO 81201
800-254-1306; 719-539-3531 fax
S&S Aqua Farm believes their Bioponic approach to integrated food production is practical and worth emulating. At a time when "biotechnology" has come to mean DNA splicing, gene engineering and cloning big corporate labs—all "hot button" controversies—Tom and Paula have redefined this word as safe, sensible, human scale, sustainable, and user friendly. And rather than closely guarding their own patented secrets, they happily share their experiences, insights—even their cultures—with other curious, independent pioneers seeking a safe path to a non-toxic world.
And in our world where water pollution, red tide and overfishing of oceans threaten our supplies of fish for food, Bioponics promises a simple, adaptable technology to raise ample amounts of high quality animal protein without the risk, costs and fuss of conventional farming, chemical fish farming and greenhouse hydroponics.
And maybe we can apply the insights gained in such simple systems—and the intuition developed maintaining them—to the restoration of larger planetary ecosystems.
However, their's is no turnkey system, or prepackaged, get-rich-quick scheme. Significant skill and knowledge are required, and a modest investment in equipment. But with a reasonable investment and experience, anyone can learn to build and sustain this productive food producing system.
To minimize "trial and error," and allow anyone to quickly start a successful system, Tom and Paula put what they learned in an information package to specify how to set up a system, whether for family food, or profitable business.
- System Mechanics
- Background and Theory
- Sample System Layouts
- Materials and Equipment Specs
- Suggested Suppliers
- Detailed Drawings of equipment placement and water flow
- Troubleshooting Guide
- Resources and Information Sources