Sources of nitrite in culture ponds:
(1) The water source contains ammonia nitrogen, and the ammonia nitrogen that has not been completely oxidized after aeration will be converted to nitrite;
(2) There are too many organic wastes such as residual bait, excrement, animal and plant corpses in the pond, and nitrites will also be produced in the process of converting organic nitrogen into inorganic nitrogen;
(3) Fertilizer selection is not correct when fertilizer water, many farmers choose to use farm manure and chemical fertilizer for fertilizer water in order to save costs, especially unfermented manure is more likely to cause nitrite rise;
(4) There is a lot of silt at the bottom of the pond, and the silt contains a large amount of organic nitrogen sources, which will produce ammonia nitrogen and nitrous nitrogen under the action of microbial fermentation;
(5) Violent changes in the weather, causing water hypoxia, bottom deterioration, inverted algae and other phenomena, will also lead to nitrite increase.
Hazards of nitrites to leeches:
(1) Nitrite will cause leeches to lack oxygen, the phenomenon of floating heads and swimming ponds, and cause leeches to die when severe;
(2) If the nitrite is high at the seedling stage, it will lead to slow or stopped development of leeches;
(3) Living in an environment high in nitrite for a long time will lead to a decline in the immunity of leeches, which will cause other diseases.
Leech Bio Tips:
(1) The lower the pH, the higher the toxicity of nitrite;
(2) The higher the hardness and salinity of the water, the lower the toxicity of nitrite;
(3) The toxicity of nitrite in seawater is much lower than that of freshwater.
Response:
It is recommended to regularly use water transfer products for adjustment, such as: first change the bottom - then detoxification - and then use fungal products, which can effectively stabilize the water quality and prevent nitrites and other excesses.