There are two ways to store alum in white water. One is to peel off the shell from the well-selected good quality and lay it layer by layer in the cylinder or pool, 15 to 20 centimeters away from the mouth of the container, and then use the disinfected bamboo to be trapped in the shape of a well. On the stones, pour in alum water to make the water 10 to 15 centimeters higher than white. Alum water is made by stirring 0.5 to 0.6 kg of alum per 50 kg of clear water until dissolved. The other is shell storage, which requires the same as the water reservoir. Stacking methods and water consumption are similar to those described above. In management, it takes 3 to 4 days to inspect once and it is found that there is foam on the water surface and it should be promptly removed. If the foam is too much, the color of the water is yellow and it must be replaced in time to prevent white rot.