Known as Taiwan red tilapia or hybrid between 0. homorum with 0. mossombicus named florida red tilapia fish. Some suspect that the red tilapia is a mutant of the fish mujair. These fish into Indonesia in 1981 from the Philippines and in 1989 from Thailand.
Red tilapia cultivation has developed in some areas, even the production has been exported to Europe and the United States. White flesh and thick. It felt good, like red snapper. In some European countries, meat red tilapia utilized as a substitute for red snapper meat.
In cultivation, red tilapia fish have an advantage among others) of red tilapia fish response to artificial feed, 2) rapid growth, 3) can live in conditions of high density, 4) value of the ratio between feed consumption and the resulting meat is lower, 5) resistant to disease and water environment is inadequate, 6) sense of the meat tasty and much-loved community.
A. Systematics
Family: Chiclidae
Species: Oreochromis-niloticus
Trade names: red tilapia
Local Name: snapper merapi, mujarah
B. Darts characteristics Aspects Biology
1. Physical characteristics
Fish body rather round and flat. The mouth is situated at the end of the head (terminal). Rib line (linea lateralis) cut in half and lay lengthwise starting from the pectoral fin. Number of scales rib line as much as 34 units. Plain reddish body color or black-spotted, spots, and often colored albino (albino).
2. Growth and development
Red tilapia breed and are rapidly growing. In addition, these fish have a high tolerance for salinity changes until 30 promil. First maturity is reached at age 4-6 months with a weight of 100-250 g. These fish can breed 6-7 times / year.
A mother can produce as many eggs from 1000 to 1500 grains. When spawning the male fish will make a nest and guard it. The fertilized egg incubated by the female parent in the mouth. Guarding by females was continued until a week after the eggs are hatched.
Karamba in the floating net fish can reach sizes over 250 g in 4 months from the initial weight of about 20 g. male fish grow faster and larger than females.
C. Cultivation Site Selection
as belonging eurihalin fish, red tilapia fish can be cultivated in freshwater, brackish, and sea. However, in waters with high salinity (> 29 ppt) of this fish is still growing well, but can not breed. Red tilapia can grow well in temperate aquatic environment between 27-33 degrees Celsius; dissolved oxygen levels> 3 mg / l; a pH 7-8,3; alkalinity 90 to 190 mg / l; hardness 62-79 mg CaCO 3, the speed current 10-2o cm / dt, the brightness of> 3 m, and the depth of water 10-20 M.
D. Container Cultivation
Raft as the Karamba (where the fish in a lake or dam in the form of nets) can be made of wood, stainless steel pipe, or bamboo. Buoy plastic drum volume of 200 liters. KJA unit for measuring 5 m x 5 m,
requires 8-9 Buoy karamaba made from net material of polyethylene. Net eye size depending on the size of fish that will be maintained. In every corner of Karamba should be weighted by a stone or cast concrete weighing 2-5 kg. Anchor required to maintain the functioning of the raft drifted to avoid. Anchor can be made from metal, wood, and cement castings.
E. Cultivation Management
1. Provision of seeds
Seeding of red tilapia is generally directed to produce female seeds mixed male. Given the male fish have a larger size and speed of faster growth, many farmers led to the cultivation of red tilapia males. Therefore, the cultivation of fisheries experts have sought to create a red tilapia seeding technology with the use of male hormones 60 mg of mixed metiltestosteron
into 1 kg of feed larvae. Sex over the process lasts for 28 days
Transporting seeds should be done with an open system if it takes less than 4 hours. In the meantime, if more than 4 hours, transportation can be done with a closed system using a plastic bag which added oxygen.
2. Spreading
Spreading the seeds performed in the morning or late afternoon so the air condition is not too hot. Before stocking, be aware of water quality conditions. If the water quality of different transportation with locations of water quality cultivation, adaptation needs to be done slowly, especially for salinity and temperature. Solid optimal stocking to be applied is 500 ekor/m3 with initial weights 15-20 g of seeds per head and 3-month maintenance time for single-sex culture systems (males only).
3. Feeding
At the time this young fish-eating plankton, both vegetable and animal plankton. Adult red tilapia fish started to eat detritus and algae are also common threads. In addition to be herbivore, omnivore fish that can be given artificial feed (pellets). These fish response, the artificial feed (pellets), either sunk or floating pellets. Artificial feed is given pellets with 26-28% protein content as much as 3% of body weight per day. Frequency of administration 3 times a day, ie morning, noon and night.
F. Controlling Pests and Diseases
To know which way the disease and its prevention, diagnosis required symptoms. Symptoms of the disease for red tilapia fish cultivated can be observed by following signs tent.
a) Symptoms of skin disease
- Color red in certain parts.
- Skin changes color became more pale.
- The body slimy.
Control
1) Soaking the fish in a solution of PK (potassium permanganate) for 30-60 minutes at a dose of 2 g/10 l of water. Treatment done over 3 days later.
2) Soaking the fish with Negovon (potassium permanganate) for 3 minutes with a dose of 2-3,5%.
b) disease in the gills
Symptoms
- Close the swollen gills.
- Sheet gills pale / white.
Control
- How to control the same as skin diseases.
c) Diseases of the organs in the phenomenon
- The fish's stomach was swollen.
- Scales up.
- Fish is not nimble.
Control
- How to control the same as skin diseases.
The general things can be done to prevent diseases in the cultivation of red tilapia fish in the KJA is as follows.
1. Avoid over-stocking of fish exceeds capacity.
2. Give grazing, both quality and quantity.
3. Avoid the use of feed that is moldy.
G. Harvest
Red tilapia fish are maintained by stocking compact 500 ekor/m3 can be harvested after 3 months. Production and 85 kg/m3 Survival rate 85%. Harvesting fish in the KJA easy to do. Harvesting systems can be either total or selective depending on the needs.
Harvesting should be done carefully to prevent injury due to friction or other fish fin puncture. How to harvest is the basis Karamba slowly lifted. However, one side of the Karamba must remain in the water allowing fish gathered WAY. After that, the fish that have been collected and selected side karamba arrested using seser slowly.
source: Penebar Swadaya, 2008
