The cultivation pool is close to the water source, with plenty of water, fresh water, no pollution, convenient drainage and drainage, and a convenient earthen pond. Independent Tongkou or in the middle of the Datang can be built, the cultivation pond to remove silt. At the outlet, dig a set of crab troughs with a size of 2 square meters and a depth of 80 centimeters. The slope ratio of Tanggu is 1:2-3. A 60-cm-high calcium plastic plate or aluminum plate is used around the pond as a means to prevent escape, and wood and bamboo piles are used as supports for the escape prevention facilities. It is advisable to use a rectangle that is long in the east-west direction and short in the north-south direction. The area is 600-2000 square meters, and the water depth is 0.8-1.2 meters. The water quality should be in accordance with the relevant feeding regulations. The following preparatory work should be done before laying the seedlings.
Qingtang Disinfection In early April, fill the water with a dense net to trap and trap and kill predators. One week later, the pool water was drained. Fresh water was re-injected from late April and disinfected with quicklime at an amount of 0.2 kg/m2.
Set water crab grass seedlings in front of the pond with a screen along the edge of the pool to place a straw, blocking surface is at least 1/3 of the breeding pond area, to provide attachment for the crab shell clam shell habitat.
The aeration facility is equipped with a 0.75-kilowatt oxygenation pump. The pump is equipped with two white plastic ventilation tubes in the pond. A uniform vent hole is attached to the vent tube and it is approximately 10 cm from the bottom of the tank when installed.
Apply fertilized water 7-15 days before seedlings and add 10 cm of fresh water. Breeding old ponds, fertilizers at the bottom of the pond, applying 2 to 2.5 kg of calcium phosphate per 667 square meters and splashing water to Quanchipi. The newly excavated ponds will add 0.5 kg of urea per 667 square meters, or 150-250 kg of fermented organic fertilizer (cattle manure, pig manure, chicken manure) per 667 m2.
Before adding the new water to the seedlings, fill the filtered fresh water so that the water depth in the cultivation pond reaches 20-30 cm, and the new water accounts for 50%-70%. After adding water, adjust the water color to yellowish-brown or yellow-green. When the seedlings are released, the water level is increased to 60-80 cm and the transparency is 50 cm. When the crab seedlings are in the pond, algae predominate, and rotifers and small branches are also included.
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