Eels have high requirements for water quality, so attention should be paid to the regulation of water quality in eel culture. Before stocking, most mud ponds were cleaned and disinfected with quicklime 150-250kg/ mu, and the pool water was 30-40k g/ mu. Disinfection at the depth of cm can increase the ph value of pond water to above 1 1, which can not only remove wild fish and insects in the water, but also improve the acidity of the soil at the bottom of the pond. Fill the water to a suitable depth, and the ph will drop to 8-9 after 15-20 days. After testing the water (using fish as trial culture), the eel can be released after the toxicity of lime disappears. If the ph value is too high (the toxicity of lime has not completely disappeared), eels will be released, leading to debonding and death. ?

The water quality is required to be "light green" and "refreshing" during the breeding process. There should be an appropriate amount of blue-green algae in aquaculture water, which can play a role in shading, increasing oxygen and stabilizing water quality. Sometimes the water quality is thin and turbid, or zooplankton multiply in large numbers, which will destroy the water quality and make algae unable to grow normally; Sometimes there are few algae in the water, which makes the water thinner and affects the feeding and growth of eels. At this time, the methods of "introduction" and fertilization can be adopted, and at the same time, the water-retaining king (photosynthetic bacteria) 2-3× 10-6 can be activated in the sun for 1-2 hours, and then sprinkled in the whole pond, which can promote the rapid propagation of algae. After using algaecide, the water quality is easy to change due to the death of algae, so it is necessary to pay attention to increasing oxygen and regulating water quality. ?

Various indexes of pool water, such as dissolved oxygen, ammonia nitrogen, nitrite, ph value, etc. , are often tested, and the water quality analysis box can be used for simple determination. If the dissolved oxygen is insufficient, it is necessary to increase the number and time of aerators, replace fresh water or apply aerators to keep the water body full of dissolved oxygen. When the ammonia nitrogen is high, it can be sprayed in the whole pool with Baoshuiwang 2-3× 10-6 or Yichibao 0.2-0.35× 10-6. These microbial agents are safe to use, can quickly decompose organic matter in water and reduce ammonia nitrogen. The content of nitrite is high, and the content of nitrite can be quickly reduced by using denitrifying bacteria preparation.

Always maintain a good water quality environment, eels eat normally, reduce the occurrence of diseases and grow rapidly, otherwise eels eat poorly, suffer from various diseases, grow slowly and have high feed coefficient. Insisting on the use of microbial agents is the most effective way to maintain good water quality, which is safe and practical and conforms to the development trend of environmental protection, health and pollution-free aquaculture. ?