The first article about S&S Aqua Farm appeared in the June 1992 issue of "Small Farm Today", others have been published in such places as "Back Home" magazine (Summer 1993) and "Missouri Conservationist" (August 1993). John Wesley Smith wrote about S&S Aqua Farm for "The Growing Edge" (Vol. 5, No. 2, Winter 1993-94).
ABOUT OUR SYSTEM
Ours is a simple, reliable, low-cost growing system used to produce a supply of safe, superior quality foods. We integrate hydroponics and aquaculture in a closed system to produce premium tilapia and fresh herbs and vegetables. Although creative, this method of food production is no mere novelty. It is a low-cost, no nonsense system.
Complex synergistic relationships take place in an uncomplicated setting. It seems the more natural we can make it, the better it works. The effluent from the fish tanks is not filtered or purified before reaching the growing beds. Some similar systems are based on a hydroponics mindset and purify the water to go through expensive feeder lines and emitters. In our system the growing beds are in effect fluidized bed bioreactors (a most efficient biofilter for water filtration) using commonly available materials, without the need for separators and clarifiers for solids removal.
Each growing bed contains pea gravel as a growing media. Effluent trickles through and down the length of the growing bed before being pumped back into the tanks. The plants get all the nutrients they need, while bacteria in the gravel remove harmful ammonia produced by the fish, perpetuating the water purification process. Fish must never be left without plants in the growing beds or water purification stops; the growing beds should never be permitted to dry out or bacteria in the gravel, essential for the purification process, would die.
Simple to Operate
You supply the water and electricity.
You feed the fish.
The fish feed the plants.
The plants take care of the fish in return.
Plants get what they need without the fuss of mixing chemicals. The unfiltered effluent (nutrient solution) is pumped straight to the growing beds through 1-inch PVC pipe.
After the initial effluent is pumped from each tank, the return through the beds takes from 10 to 30 minutes. A bucket containing a pump in each node holds 10 to 15 gallons. When this fills up, the water is pumped back into the tank and forced through a PVC cap drilled with numerous 1/4 inch holes, creating a showerhead effect. This oxygenates the water to optimum levels for the tilapia. Additional aeration is unnecessary.
IMAGINE GARDENING YEAR-ROUND WITH NO WEEDS TO PULL, NO BENDING FOR PLANTING OR HARVESTING, NO WORRIES ABOUT WATERING OR THE WEATHER.
PICTURE YOURSELF IN MID-WINTER WORKING IN A GREEN, VITAL, HEALTHY ENVIRONMENT - DOING SOMETHING YOU LOVE TO DO.
The system is simple and revolutionary for the very reason that it does not make use of technology normally assumed to be necessary for aquaculture, hydroponics, or both.
The system is flexible. A "node" is a tank of fish connected to one or more growing beds. A node can be constructed small enough to fit into a kitchen, one or more nodes could fit into a backyard greenhouse, or any number of large nodes could function in commercial greenhouse operations.
In addition to flexibility of size and simplicity of operation, the system is environmentally friendly. There is no effluent runoff. Plants and bacteria in the gravel beds use nutrients in effluent and purify the water for the benefit of the fish.
There is no mixing of fertilizers for hydroponic production, and the synergistic relationship between plants and fish actually necessitates the use of NO chemical pesticides or medications. Clean, pure and wholesome food is the result.
From a system point of view there are three main components of the operation - fish, plants and bacteria. The rest of the hardware items are there to optimize the life cycle of each of the three main components.
ABOUT THE FISH
Tilapia, a fish that produces delicious white flesh with few bones, are a hardy, disease resistant, warm-water fish. They're native to Africa and the Middle East and have been raised for food since the days of the ancient Egyptians. Some believe Christ fed tilapia to the multitudes. Tilapia is the most popular fish for culture in the world.
Tilapia are fast growing, reaching 1 to 1-1/2 pounds by 9 to 18 months, are extremely disease resistant, and will provide firm, white boneless fillets (approximately 40% by weight). They are readily marketable at 3/4 pound and up. We prefer to sell our fish at over one pound live weight - most generally at a pound and a half.
The feed conversion rate for this fish is excellent, with one pound of feed yielding one pound of fish. Tilapia devour algae in addition to their regular feed, and excess plant cuttings add to this nutrient source. In addition, they will tolerate low oxygen and poor water conditions that would kill most other fish. We have found them to be extremely hardy.
ABOUT THE PLANTS
Currently we are producing lettuces and salad greens for local restaurants and subscribers for our own specialty mix. Our retail sales are primarily on a subscriber, or pre-order basis, with excess being sold at the local Farmers Market. Additionally, we are now producing some value-added products.
We have experimented with many different types of plants - ornamentals, herbs and vegetables. Most attempts have been successful. We've grown from seed, from seedlings, from cuttings. We've produced food crops, rooted cuttings, fresh cut herbs, and become our own supplier of starts for flowering basket sales. We're excited about what this system can do!
Plants grow in half to one-third the time required for plants grown by conventional methods.
Cuttings from almost any plant (including trees) will root and grow if placed into a growing bed and exposed to the nutrient-rich water, with NO rooting hormones or chemicals.
ABOUT THE BACTERIA
A healthy bacterial culture is a necessity in this system and the limit on how many fish you can maintain will be gaited by the health and growth rate of your bacteria. What do bacteria need? They need warmth, moisture, dark and oxygen. All these are present in our system except for the surface area of the growing beds.
Plants alone do not purify the water for the fish. They only take up the nutrients that the bacteria put out after they work on and convert the fish wastes. The bacteria are a critical element in the system and should be treated with proper respect. Take steps to insure a good oxygen supply. Aeration of the fish water by the methods we prescribe, and cultivation of the growing beds when empty will provide more dissolved oxygen for the fish, as well as provide an improved oxygen level for the bacteria and plants.
There is no effluent discharge from our system, making it environmentally friendly. Due to the recirculation and efficient reuse of water, only 7 to 7.5 percent of the water must be replaced per month as a result of evaporation and plant uptake.
We believe in growing as naturally as possible, but our system also demands it. Any pesticides sprayed on the plants would find their way back into the fish. Any antibiotics poured into the fish tanks to treat diseases would find their way to the plants and kill the bacteria. Predatory wasps, ladybugs, lacewings, Bt and other specific organically approved methods are used to control whiteflies, aphids and other pests and diseases that affect the plants.
A minimum of electricity is used because the solar greenhouse design doesn't require it. We do all we can to maximize the use of solar energy. The fish tanks are black to absorb and retain heat. Warm water, a high level of nutrients, CO2 from the fish, and frequent flow are what allow us to grow all through the winter.
LOW COST MATERIALS
Basic items for operation consist of:
A building - the system can be adapted to suit most any greenhouse style and size.
Tanks - we use hatchery tanks from PolyTank.*
Growing beds - may be as simple as wood, lined with plastic or as durable as prefab poly.*
Pumps - common submersible sump pumps are recommended
PVC piping and fittings
Gravel - it's an efficient grow media. It's also low-cost, low-maintenance, and readily available in most locations.
ADD fish, plants and bacteria - the three main system components.
*PolyTank, our tank supplier, now manufactures 4'X8' growing beds of the same material as our tanks (no maintenance, and virtually indestructible).
Basic operating costs will include:
Seeds and plants
Our system is unique.
The system's design offers flexibility.
It can be operated on a small scale or in a large commercial set-up.
Parts and equipment are readily obtainable, most from local suppliers.
Elements in nature enable the system to function successfully, not some exclusively patented device.
WHAT WE OFFER
We believe our approach to integrated food production is practical and worth emulating. We can provide vital information you'll need to set up your own system, whether you want extra food for your family or want to start your own profitable business. NOTE: This is not a turnkey system or prepackaged, get-rich-quick scheme. What we offer is an information package. For more details, click on the PKG INFO button.