Commercial Tilapia fish farming is becoming popular day by day as demand grows for this fish. Basically, Tilapia is the second most farmed fish in the world. Tilapia fish has contributed substantially to Food Security. The world aquaculture production of Tilapia fish is 4.2 million tonnes with an estimated value of around 3 to $ 3.5 billion. When it comes to the potential of Tilapia fish farming, generally, low-laying areas with water stagnation are suitable for agricultural activities. Tilapia fish is among the easiest and most profitable fish to farm due to their omnivorous diet, and mode of reproduction. Tilapia fish farming in tanks or channels is considered safe for the environment since their waste and disease are contained and not spread to the wild. Here are the tips:
Selection of Pond:- Select the pond or tank with a minimum water depth of 1.5 to 2 meters. Make sure that the water level never falls down below 1 meter. The main criterion to be kept in mind is that the selected pond soil should be water retentive and sufficient water supply is assured. Avoid flood-prone areas, industrial areas and chemically impacted soils. If you are selecting old ponds, they can be renovated for fish culture by dewatering, repair of the embankments and provision of inlet and outlet. In either case of ponds (new or old), the following should be done for the development of the pond.
- Excavation/Digging of new ponds should be carried out.
- In the case of existing shallow ponds, deepen the shallow ponds.
- Desilting of existing ponds should be carried out.
- Impoundment of marginal areas of water bodies should be carried out.
- Construction of Inlets / Outlets should be carried out.
- Construction/repairs of embankments should be carried out.
- Construct/ repair any civil structures, watchmen rooms, water supply arrangements/electricity supply.
Bio Security:- Bio-security measures should be in place to ensure no escape of the Tilapia fish or biological material from the farm/pond to the other water source. The following important bio-security measures should be taken care of for safe Tilapia fish culture.
- Outlet water from fish ponds must be screened and treated before being released into drains/canals/rivers during culture practice or subsequent to harvesting in order to prevent the escape of fish eggs into natural water bodies.
- Provide bird scaring device/fencing securing the pond.
- Make sure that the bund height is high enough to avoid fish escaping from the pond.
- Arrange sluice gates with an appropriate mesh size to prevent the escape of fish, eggs, and fry.
- In case of flooding, make sure to secure the pond so that the fish or fry will not escape from the pond to other water sources
Pond Management:- Pond management plays a critical role before and after stocking the fish. Various measures should be carried out as part of pond management. The following are the fish pond management activities.
- Pre stocking:- In the case of new ponds, pre-stocking starts with liming and filling the water.
- In the case of existing ponds, any unwanted weeds and fish should be cleared by manual, mechanical or chemical means.
- Unwanted and predatory fishes and other animals should be removed by repeated netting or by sun-drying the pond bed for a couple of days.
- Liming:- The fish ponds which are acidic in nature are less productive than alkaline ponds. However, lime is used to bring the pH to the desired level for better production. Apart from this, lime has other benefits as mentioned below.
- Lime increases the pH level.
- Lime acts as a buffer and avoids fluctuations in pH.
- Lime increases the resistance of soil to parasites.
- Lime’s toxic effect kills the parasites and lime speeds up organic decomposition.
- If you are planning to go for commercial fish farming, the soil should be tested. On average, 225 to 250 kg/ha of lime is required to cover the 1-hectare pond. However, the actual dose depends on the pH of the soil and water.
- In the case of a new pond, the pond should be filled with water after liming application.
Fertilisation:- Fertilization should be carried out depending on the soil quality in the pond. A combination of both organic and inorganic fertilizers may be used for best results. The fertilization schedule has to be prepared and can be modified depending on the growth of the fish.
- Organic Application:
- Organic manure is to be applied after a gap of 3 days from the date of liming.
- Cow-dung at 5000 kg/ha may be applied.
- The requirement of nitrogenous and phosphate fertilizers would vary as per the nature of the soil fertility indicated below.
- Inorganic Application:
- Stocking:- The fish pond will be ready for stocking after 2 weeks of application of fertilizers. Tilapia fry (small fish) can be procured from the approved hatcheries.
- Nursery Rearing:- The Tilapia fry should be reared in nursery ponds at least a month before they come to the actual pond.
- The nursery rearing can be done in nylon meshed hapas suspended in grow-out ponds. 50 – 80 fry may be reared in one square meter.
- Feeding can be done using small floating pellets and the feeding can be reduced from 30% to 20% of the bodyweight as the fish grows and moved into the grow-out pond.
- Special feeds can be bought from the market. The Tilapia fries should be fed at least 3 – 4 times a day based on the demand for feed to get good survival and growth.
- The ‘hapa’ should be cleaned regularly to facilitate water flow.
- After rearing for one month in nursery ponds, Tilapia can be released into an actual growing pond with a stocking density of 3-6 No’s /sq. meter for better development and survival.
- Post Stocking:-
- Supplementary Feeding: Generally, any fish needs much more feed than what is available in the pond or tank. However, Tilapia fish can be fed with artificial feed and floating pelleted feed. A commercial feed with a Feed Conversion Rate of 1.25 to 1.5 is ideally preferred.
- Manuring: Organic Manuring may be applied in monthly instalments @ 900-1000 kg/ha and inorganic fertilization may be applied at monthly intervals alternating with organic Manuring. However, the monthly rate of fertilization will depend on pond productivity and the growth of the Tilapia fish. Make sure that excess fertilization does not take place which may result in eutrophication.
- Monitoring: Periodical monitoring of the fish to be carried out for disease incidence and growth. Records for day to day management of the pond are to be kept for inspection.
- Harvest: Harvesting of the Tilapia fish is generally done at the end of 5 to 6 months when the fish attains an average weight of 500 to 600 grams in 5-6 months. A production of 8 – 10 tons/ha can be obtained in one crop of 6 months.
Harvesting should be done by partial dewatering and repeated netting. Based on the market demand, fish farmers can sell the live fish to the market or can be frozen and exported to international markets.
Source: Agriculture Nigeria