Scaly diseases are generally divided into low-temperature scales and bacterial scales. Bacterial scales include bacterial scales caused by visceral system infection and bacterial scales caused by body surface infection. Scaling caused by changing water at low temperature will not be obvious after you change water, but it will be obvious the next day after changing water. This problem has been basically solved. There are several ways to deal with the scaling caused by changing water. The first one is that scaling will immediately adjust the heating system in the water tank to 33-34 degrees. This method may be restored as soon as possible on the same day, but it also needs to last for 3 days in high temperature environment. There is a second method, which is to treat common diseases with the old three kinds. I believe there is no need to go into details about the methods used, which generally have a good effect on the initial scaling. Then, after the temperature rises, a lot of water can be changed, basically 20/ 100 on the first day, 20/ 100 on the second day,13 on the third day and12 on the fourth day. Changing water can stimulate the recovery of scale. For bacterial cleaning, I generally suggest using the old three samples, adding a small amount of good quality yellow powder, strengthening water exchange, adding black water appropriately and turning off the lights are of great help to the treatment effect. If the scaling is caused by the visceral system, it will be more troublesome and can generally be treated with antibiotics. Of course, it is necessary to clean the cotton filter. Which one should we adopt for the above treatment of scales? This involves some problems such as individual breeding environment, water quality, water exchange, temperature, fish size and other individuals' polyculture. Therefore, each arowana has different physique, different feeding environment, different water environment and different treatment methods.