There are currently two common types of stainless steel water tanks on the market: 304 and 201. In general, SUS304 plate is commonly used for stainless steel water tanks. Compared with 201 plate, 304 stainless steel has strong corrosion resistance and good corrosion resistance to alkaline solutions and most organic and inorganic acids. 201 stainless steel contains manganese element and has a darker color than 304. Due to the different nickel content, the corrosion resistance of 201 is far inferior to that of 304, and its acid and alkali resistance is also worse than 304. 201 has a higher carbon content, is harder and more brittle, and is prone to rusting. Generally, it will rust after one year of use. In addition, in cases of poor water quality, 316 sheet steel is generally used for production, while 444 sheet stainless steel water tanks are more commonly used in coastal areas.