Tap water is the best fish culture. Usually, the fish raised are ornamental fish, which are delicate and must be raised in unpolluted water. Although river water can feed river fish, it still has certain risks for ornamental fish. The temperature of well water is relatively low, and dissolved oxygen is insufficient, which is not suitable for fish farming. After disinfection, tap water itself has no pollution, so fish farming is very good, but due to the existence of residual chlorine, it needs to be dried.

1. Trapped water: The first step to raise water is trapped water. Because tap water is usually used for fish farming at home, although this water is not polluted, it still has chlorine after disinfection, which will pose a certain threat to the health of fish, so it needs to be removed. Chlorine removal usually adopts the method of drying, but if the time is short, aeration can also be considered.

2. Filtration: In order to reduce impurities in water, keep filtering when raising water. After the trapped water is injected into the fish tank, it is usually filtered several times until the water becomes clear. After that, the filter should be turned on all the time, so as to maintain the water quality. At the same time, the flowing water body is also helpful to improve dissolved oxygen.

3. Culture of bacteria: Culture of bacteria is the most important thing in culture water. The purpose of culture bacteria is to establish nitrification system. After the decomposition of organic matter in water, ammonia nitrogen will be produced, which is a harmful substance to fish, and it can be transformed by nitrifying bacteria without harming fish.