Features:  The WiFi online pH TDS controller allows you to real time monitor the pH and TDS via your smartphone on the Tuya APP(for free), it is compatible with ios and Android system, perfect for 24 hours online monitoring.  Widely used to test the pH / Temperature / TDS (Total Dissolved Solids) of water.  With relay output power socket, you can control the pH value according to your requirements.  You can replace the fuse easily and fast with external replacement. Detachable and replaceable pH electrode.  With power plug for air outlet stone, oxygen pumps, carbon dioxide regulators, solenoid valves and other pH control devices.  Test the TDS with both PPT and PPM units at will.  Easy calibration of pH/TDS with just a mini-screwdriver and automatic temperature compensation.  Clear LCD with backlight, 3 results displayed simultaneously. Easy to use and provide instant display of results.  Test temperature in & 8451; / & 8457;(switchable units) and can online monitor and control pH for a long time.  Apply in water sources, soil-free growing, aquarium, hydroponics, laboratory, spas, environment water, swimming pools, water purification systems, etc.  APP Language Selection: English, French, German, Russian, Japanese, Korean, Spanish, Chinese, Traditional Chinese (Only supports Chinese and English in offline state)    Specifications:  Plug Type: AU / EU / US / UK (Optional)  Material: ABS  Power Supply: AC230, 50Hz (EU) / AC120V, 60Hz (US)  APP Name: Tuya  OS Requirement: Compatible with iOS and Android system    Range: pH: 0.00~14.00pH              TDS: 0~19990ppm, 0~199.0ppt              Temperature: 0~50& 8451; (32~122& 8457;)  Resolution: pH: 0.01pH                     TDS: 1ppm(1000ppm), 0.1ppt                     Temperature: 0.1& 8451;(0.2& 8457;)  Accuracy: pH: ±0.1pH                  TDS: ±2%F.S                  Temperature: ±1.0& 8451;  Alarm Setting Range: pH: 0.00~14.00pH                                   TDS: 0~20000ppm  Temperature Compensation: 0~50& 8451; (32~122& 8457;)  Operating Temperature: 0~50& 8451; (32~122& 8457;)  Length of Sensor Line: 2m / 6.56ft  pH/ORP/TEMP Controller Size: 160 * 95 * 40mm / 6.30 * 3.74 * 1.57in (Excluding Electrode Connector)  Control Socket Size: 130 * 65 * 53mm / 5.12 * 2.56 * 2.09in (Including Fuse)  Item Weight: 872g / 1.92oz  Package Weight: 1077g / 2.38lb  Package Size: 32 * 20.5 * 7.6cm / 12.60 * 8.07 * 2.