How long can butterfly koi fish recover after being frightened?

3-7 days. According to relevant data, it usually takes three to seven days for fish to recover after being frightened. Some fish have poor adaptability and may take about half a month. In the process of fish recovery, it is necessary to ensure that the environment is quiet enough to avoid aggravating the situation. Fear of fish may be caused by inadaptability to the environment, and fish can recover after a period of rest. It may also be caused by the change of water quality, so it is necessary to ensure the stability of water quality and avoid the fish from being frightened.