The main reasons for the death of koi carp include water quality issues, environmental temperature difference problems, accumulation of ammonia compounds, lack of oxygen, and improper fish selection.
Water Quality Issues
Water quality is one of the important factors affecting the health of koi carp. Tap water in some areas may contain a large amount of disinfectants and detergents, and these chemicals are toxic to koi carp. To solve this problem, you can expose the water to the sun and aerate it before changing the water, and use a dechlorinator to remove the chlorine in the water. In addition, koi carp are suitable for living in water with a relatively low hardness. Avoid suddenly moving them from soft water to hard water to prevent allergic reactions.
Environmental Temperature Difference Problems
Koi carp are very sensitive to sudden changes in water temperature. A temperature difference of more than 3 degrees Celsius may lead to their sudden death. Especially in cold weather, the temperature difference between the water temperature in the tank and the tap water is relatively large, which poses a great challenge to the koi carp. To ensure the stability of the water temperature, you can use a water heater to heat the new water to an appropriate temperature and use a thermometer for real-time monitoring.
Accumulation of Ammonia Compounds
During the metabolic process of koi carp, ammonia compounds are produced. If these wastes accumulate for a long time, it will lead to a decline in the physical condition of the koi carp, chronic poisoning, and the growth of a large number of pathogenic bacteria. To reduce the accumulation of ammonia compounds, you can carefully select the feed, add an appropriate amount of salt, use broad-spectrum antibacterial drugs, introduce nitrifying bacteria, and strengthen the filtration system.
Lack of Oxygen
When koi carp lack oxygen, they will exhibit the phenomenon of gasping at the water surface, which is a fatal symptom. To avoid lack of oxygen, it is necessary to regularly check the water quality and oxygen content, and if necessary, aerate the water or change the water.
Improper Fish Selection
When selecting koi carp, pay attention to avoid choosing fish with sunken eyes, as this may be a sign of poor health.