The GM20 low-speed well washing multi parameter system is a portable and intelligent water quality data acquisition device, specifically designed for groundwater sampling and well washing work. The samples are collected through a closed circulation pool to obtain on-site data. Its design aims to monitor turbidity, temperature pH、 ORP、 The measurement of conductivity, RDO optical dissolved oxygen and other data is more authentic and representative, and the data can be printed on site as a result report. The instrument is operated and controlled through a handheld data terminal connected wirelessly, with low-speed well cleaning software. The screen can clearly display the overall status of the device, battery life, data recording, sensor status, and connection information. Setting up programs through a mobile app suitable for Android devices makes on-site operations convenient.