What are the precautions for farming rice field eels with tap water?

As for whether tap water can be used in an eel pond, the first thing to consider is where the tap water is drawn from, and the second is how the tap water is processed and purified. If it is tap water pumped directly from a natural river and delivered to households, such water can be used for farming rice field eels. However, some tap water that has undergone chemical purification treatment or is taken from deep underground will cause the following three problems when used for farming rice field eels:

pH problem

Tap water taken from underground has a very high pH, and long-term use will cause rice field eels to suffer from chronic alkalosis. The symptoms are a blackened and bleeding mouth, shedding mucus, red and swollen anus, and a body color that appears anemic.

Chemical residue problem

Long-term use of tap water treated with chemical disinfectants such as bleaching powder and strong chlorine for farming rice field eels will cause excessive chlorine residue in the eel pond or cage, leading to cumulative poisoning in the middle and late stages of the rice field eels. Its main symptoms are liver damage in the rice field eels, and after death, obvious black blood bands on the intestinal wall.

Temperature difference problem

Whether it is tap water taken from underground or purified tap water taken from rivers and lakes, there is a large temperature difference problem when it is used. Sometimes the temperature of the tap water differs from the water body in the eel pond or cage by more than 8°C. Especially when cold air moves southward or the weather changes abruptly, the water temperature difference between the eel pond and the tap water is particularly obvious. If the temperature difference of the introduced water in the eel pond or cage exceeds ±3°C, the rice field eels will become diseased, and in severe cases it will even lead to complete failure of the rice field eel farming.

Correct methods for using tap water to farm rice field eels

Build a relatively large reservoir (a cement reservoir should be dealkalized before use), put the tap water into the reservoir and expose it to the sun for 5-7 days before use.