Detailed Explanation of Key Points of Tilapia Cage Aquaculture Technology
Tilapia tolerates low oxygen and fertile water, is afraid of cold but not heat, and will suffer cold injury when the water temperature is 12-13°C. Its survival temperature is 15-35°C, and its critical temperature is 8.61°C±0.15°C. Therefore, when choosing a site in a reservoir, it is essential to choose the side with fertile water quality, shelter from wind, sunny exposure, and higher air temperature, and not to place it at the wind outlet of the reservoir.
Cage Structure and Layout
Cages can be made 1 m×1 m×1 m in size, with a mesh size of 3 cm. The bottom of the cage is made of fine mesh cloth into a dish-shaped bottom net with a side height of 20 cm to prevent feed loss. At 50-30 cm above the top of the fully enclosed cage, install one insect-attracting lamp, and at one corner of the cage cover set up a black plastic inclined insertion pipe or black iron sheet pipe with a diameter of 10 cm as a feeding pipe. Use moso bamboo (10 cm in diameter) as the overall frame of the cage, and use black woven material, etc. on top of the cage to make a cap slightly larger than the cage cover, used to shade the tilapia in the cage from light, avoid external human disturbance, avoid animal disturbance, and protect the fish's safe feeding. In a dark environment, the fish's activity is greatly reduced, which is beneficial to growth. The spacing between cages is 2-3 m, arranged in a triangular pattern.
Stocking Time
Fish fry can be stocked when the water temperature is about 24°C. Water temperature below 20°C easily causes cold injury to the fish body. Therefore, stocking after the air temperature is stable at 20°C is beneficial for the fish to start feeding early.
Stocking Density
For tilapia with a body weight of about 40 g each, stock 330-550 fish per square meter of cage.
Feeding Method
Fish newly entering the cage should be fed a small amount of highly palatable feed for domestication. After a few days, feed steadily, 4 times a day. A water temperature of 28-32°C is the golden water temperature for tilapia feeding, so feed more. Mixing Chinese herbal medicine into the feed is often a key point for disease prevention. In seasons with flying insects, uncover the cage cover at night, turn on the lamp to attract insects to feed the fish, and put the cage cover back on during the day. Do not injure the fish body and do not cause disease; fish eating insects is most useful. The cage cover creates a dark environment; when the water is good, the fish grow continuously.