The square stainless steel water tank is made of 304/316L food contact grade material and has passed relevant certifications for food contact materials. The inner wall is smooth and easy to clean, reducing sanitary dead corners. It supports customization of 5-200 tons capacity, uses a rounded corner design to reduce water residue, is equipped with a CIP cleaning interface to facilitate regular disinfection, and provides door-to-door installation location services based on the production process.