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Have you ever wanted to grow your own fish?
Do you have a desire to raise your own food for a more self-reliant and healthy lifestyle?
Well then, farming tilapia may be for you.
Tilapia are warmwater, hardy fish that are easy to grow. You don’t have to have a “blue” thumb, but it helps to do some planning before you launch into tilapia farming. You want to set up a growing system that is easy to maintain and that will fit your lifestyle.
Tilapia are good to eat and have mild, white fillets. There are hundreds of tilapia recipes, so that you can create new, healthy meals for your household. Fresh tilapia are in demand, not only for home consumption, but by restaurants and seafood outlets.
Tilapia are often grown along with vegetables in aquaponic systems. The nutrients from tilapia waste can be used by the vegetables (lettuce, kale, tomatos, cucumbers, and other plants) for growth and this helps to purify the water.
Here are 7 steps that will help you start growing tilapia:
1. Take a quick inventory of your personal motives and readiness.
Why do you want to raise tilapia? Determine what your goal is. Are you looking to grow fish to feed your family?
If you grow enough fish, will you barter them with your neighbors for other goods or services? Do you want to sell them at a local farmers market? Do you want to learn tilapia aquafarming on a small scale before venturing into a larger, commercial enterprise?
What resources do you have?
Do you have a source of water available to you. For example a farm pond or stream on your property. Don’t worry if you don’t have a natural water source available. Tilapia are freshwater fish and have been grown successfully in conditioned tap water.
Do you have materials available that you can use as part of your farming efforts. You don’t need a fortune to start growing tilapia, but you must likely will need a modest budget to purchase fish and some other items.
Look at ways to use the resources you have at hand. For example, a plastic child’s swimming pool may be the perfect “tank” to hold your first crop of fish.
Can you learn fish rearing techniques? Tilapia are easy to grow, but it will take some education on your part to learn about how to raise these fish successfully.
If your personal assessment confirms that raising tilapia is for you, then continue on to following steps.
2. Find out about your local regulations.
Before you begin raising tilapia, even for home consumption, you should check with your state authorities to determine if there are any specific regulations on obtaining and possessing tilapia. Each state has its own guidelines.
You may also be able to get assistance on growing tilapia from your state’s aquaculture extension agent.
If you intend to sell the fish you raise, then you will want to organize your business. You can register as either sole-proprietorship, partnership, corporation or LLC.
For business ventures, there may also be a commercial license, operating permit, and other requirements that may be required by the state.
CAUTION: Tilapia are invasive fish and can quickly displace native fish populations if you introduce them into natural water bodies. You must take care to make sure you properly dispose of any live fish or waste water containing eggs or juvenile file. Any fish that you don’t consume can make ideal compost if added to your home garden.
3. Develop a plan and budget.
Take the time to develop a plan for how you will raise your tilipia. This does not have to be a formal plan or even written down, but you do need to think about the following items:
How will you learn about culturing tilapia? For example, will you purchase a book, contact your state’s extension agent, use online resources, or attend a course on tilapia culture.
What is your budget? The amount of money you have available for your project will have a bearing on whether you purchase materials new or used, or whether you try to improvise using materials you already have.
Do you need to purchase items, such as a tank, biofilter, aerator, nets, feed or other equipment? If so, where will you get them?
How will you maintain your fish? What will you feed them and when? How will you maintain the proper levels of dissolved oxygen, carbon dioxide, pH, and nitrogen compounds present in water? How will you keep these warmwater fish at the proper temperature? Tilapia are able to withstand a range of environmental conditions, but you do need to try to optimize their growing conditions for best results.
Do you intend to breed fish so that you can avoid having to purchase fry or fingerlings? If so, what type of hatchery system will you use?
What will you do when fish are ready to harvest? Do you intend to use them for your household food or sell them to local markets?
4. Set up your tilapia system.
Tilapia can be grown successfully in a variety of environments, including ponds, cages, raceways, and tanks. Urban farmers have even reported growing them in trash cans.
Growing fish in a pond is perhaps the simplest method. You may even be able to allow the fish to feed on the natural food available in the pond
If you are using a tank or cage, you will need to purchase the materials needed to set up these systems. If you are using tanks, especially where the water is not being recirculated, you may need to condition the water for a few days before introducing your fish.
So set up your culture environment. It is probably best to start small and evolve into a larger system, as your experience grows.
5. Get fish to start your farm.
Now that you have your culture environment ready to go, it is time to introduce fish into your system for growout. Typically, you will purchase tilapia fingerlings (juvenile fish in range of 0.75″ to 2.0″). Find a reputable dealer to purchase your fish from.
After you receive your fingerlings, you may need to acclimatize your fingerlings slowly to the temperature, pH, and general water conditions of the growout environment. Introduce your new crop of fish into the growout environment and begin farming.
Note: You may also purchase fry (fish less than 0.75″), but they require more attention for their growout.
6. Grow your fish to harvestable size.
During the growout phase you need to feed your fish and maintain favorable environmental conditions.
The best growth occurs when water chemistry is maintained within an optimal range. For tilapia, the recommended water chemistry values are as follows:
Temperature: 80-100°F, 85°F is optimal
(Note: tilapia will slow their eating at 75°F, will become weak at 60°F and die at 50°F)
Dissolved Oxygen: 5-7 ppm (parts per million)
Free Ammonia (not total ammonia): optimal=0, 2ppm will kill, 1ppm will slow growth.
Nitrite: 0.3 mg/l or less
Nitrate: 200-300 ppm
CO2: 20 mg/l or less
Just like growing a traditional vegetable garden requires proper care and maintenance, you will need to watch over your “aquacrop” to promote optimal growth. Under proper growth conditions, tilapia will reach harvestable size in 4-6 months.
In addition to raising your fish for food, you may want to set aside some of your adult fish as breeders to produce fry and fingerlings to “reseed” your fish crop for another harvest. This is truly the way to make your tilapia farm self-sustaining.
7. Harvest your fish.
After the growout phase, your fish are ready for harvesting and you can start to enjoy the fruits of your labors. Find some interesting new tilapia recipes and prepare some healthy, tasty meals for your family to enjoy.
If you intend to sell you fish, then initiate your tilapia marketing and sales program.
To Learn More
Tilapia are able to withstand a wide range of environmental conditions, including high salinity, high temperatures, high ammonia concentrations, and low oxygen levels. This makes tilapia very suitable for aquafarming.
Although tilapia are freshwater fish, they can grow in elevated salinity conditions.
Salinity Tolerance for Growth
|Nile Tilapia||Grows well at salinities up to 15 ppt|
|Blue Tilapia||Grows well at salinities up to 20 ppt|
|Mozambique Tilapia||Grows well at salinities approaching seawater|
Tilapia spawning is best in lower salinities. The fry perform better at salinities
less than 5 ppt.
Salinity Tolerance for Reproduction
|Nile Tilapia||Reproduce well at salinities up to 5-10 ppt|
|Blue Tilapia||Reproduce well at salinities up to 5-10 ppt|
|Mozambique Tilapia||Reproduce well at salinities up to 10-15 ppt|
Tilapia are warm water fish and usually exposing them to temperatures lower than 50 to 52° F is lethal. Blue tilapia can tolerate somewhat temperatures down to 48° F. This limits tilapia commercial farming potential in temperate regions.
|Feeding||Stops below 63° F|
|Harvesting||Stress and mortality from handling increases below 65° F|
|Reproduction||Best above 80° F, no reproduction below 68° F|
|Growth||Optimal from 82-85° F|
Tilapia are able to tolerate dissolved oxygen levels less than 0.3 mg/L, a level that would prove fatal to most other farmed fish.
Although tilapia can tolerate low oxygen levels, they grow best when oxygen levels are kept about 1 mg/L. This may require some aeration in high density cultivation situations.
Tilapia can survive in pH ranging from 5 to 10, but optimal pH is between 6
The tilapia can tolerate high ammonia. Increasing ammonia concentrations increases the stress on the tilapia.
Effect on Tilapia
|0.08 mg/L or above||Depressed feeding|
|0.2 mg/L or above||Some mortality occurs|
|1 mg/L or above||Mortalities, particularly among fry and juveniles|
|2 mg/L or above||Massive mortality|
High concentrations of nitrate stresses fish because nitrate limits the ability of hemoglobin to transport oxygen within the body. Tilapia can tolerate higher nitrate levels than many other cultured freshwater fish.
For optimal cultivation, nitrate concentrations should be kept below 27 mg/L. To prevent nitrate problems in recirculating systems, chloride concentrations are often maintained at 100 to 150 mg/L chloride.
Popma, Thomas and Michael Masser, Tilapia: Life History and Biology, Southern
Region Aquaculture Center, Pub. No. 283, 4p.