Why is it suggested that river crab farmers plant aquatic plants a year ago?

The aquaculture of river crabs in 2017 has come to an end, and a new round of breeding is about to begin. As the saying goes, "raise water first, raise crabs first" is enough to see that water plants play a vital role in the cultivation of river crabs. The main aquatic plants planted in crab ponds are Elorella, Sophora flavescens, verticillium verticillata, and there must be a variety of aquatic plants planted in crab ponds. In Jiangsu Province, most crab ponds are mainly planted with Elorella vulgaris, which is commonly known as "eating invincible". It has strong adaptability and tolerance to low temperature. It begins to grow when the water temperature reaches 5 ℃, and it can survive the winter in cold winter. It is recommended that Elorella should be planted years ago. The main reasons for the priority growth of Elodea are as follows:

First, absorb the residual toxins from the clear pond.

The common pond cleaning drugs are quicklime, bleach, tea seed cake and pyrethroids, which should be detoxified in time to ensure the healthy growth of farmed animals. Detoxification stress essence solution (2 mu / bottle) was used for degradation pesticides, heavy metals and disinfection insecticides, and detoxification Shuangshuibao (2 mu / bag) was used for chlorine preparations such as degradable bleach, heavy metal residues and quicklime. If there are some toxins left in the ring ditch, let the aquatic plants absorb and purify after a winter.

Second, purify water quality

Elorella is rich in nutrition, which can purify water quality, prevent water eutrophication and help to create a good water quality environment. With shallow water level and great transparency in spring, fertilizer and water should be done well in advance to prevent the growth of moss. The combination of low temperature fertilizer and water (5 mu / bag) + algal peptide (2 mu / bottle) can be used for 8-10 days to stabilize the water color and prevent moss.

Third, improve the substrate.

Aquatic plants can absorb a large number of harmful ammonia nitrogen, carbon dioxide and residual food solutes and some organic decompositions in the water body. With the continuous cultivation time, insecticides such as cypermethrin and trichlorfon are used at the mouth of the pond all the year round, resulting in serious water pollution, resulting in residual toxins in the water; a large number of residual bait, feces and other organic pollutants are accumulated at the bottom of the pond, which are not decomposed thoroughly in the case of insufficient dissolved oxygen, resulting in the accumulation of ammonia nitrogen, nitrite and hydrogen sulfide toxin, resulting in slow poisoning of river crabs. Use Wei Di / Di Ju Sujie an (2-3 mu / bag) to relieve the bottom poison and eliminate pathogenic bacteria.

Fourth, improve the survival rate of crab seedlings in the coming year

Ten years ago, aquatic plants were planted, and after a winter of growth, the area of aquatic plants became larger, ensuring sufficient dissolved oxygen in the pond, providing a place for crab seedlings to live in the pond, and a place to hide when the first and second shells of river crabs were shelled. Don't increase the mortality of river crabs because of external reasons.

Nanjing Shi must get a friendly reminder: try not to use pond cleaning drugs with excessive residual toxins when clearing ponds. If you use detoxification stress essence solution in time, the early pond water color should not be too clear, and it is easy to breed moss. It is best to use low temperature fertilizer and water combination: algal peptide + algal fertilizer to fertilize water, the speed of fertilizer and water is fast, and the water color is good, which can effectively restrain the growth of moss. For the ponds that do not clear the pond all the year round, it is recommended to use Weidi or Diju Suijie'an for bottom disinfection and sterilization. Finally, I wish you every success in breeding in 2018.