The reason why the water for raising koi is muddy is that koi is large in size, so it excretes more, and it will become muddy if it is not changed in time at ordinary times. Usually, the water should be changed once a week for fish farming. If the water quality deteriorates rapidly, it can be shortened to once every three to five days. Every time the water is changed, it should be changed by about a quarter. At the same time, attention should be paid to temperature control to keep the temperature unchanged. If the temperature changes, it will also cause irritation to fish.

1. Change water regularly: To improve water quality, the most direct way will be to change water regularly. The cycle of changing water is usually not fixed, and it should be decided according to the maintenance of water quality. If the water quality deteriorates rapidly, it should be changed every three days, and if it deteriorates slowly, it can be changed only once a week.

2. Maintain filtration: Water quality is mainly maintained by filtration. Filtration consists of two parts, one is a water pump, which can make water flow, and the other is a filter box, which contains a large number of filter materials. After the water flows through the filter materials, dirty things will be filtered out, thus improving the water body.

3. Reduce feeding: In the daily feeding process, feeding too much food will also make the water body turbid and have an unpleasant smell. Therefore, feeding should be controlled at ordinary times, and it should be finished within 3-5 minutes after each feeding.