Arduino-Based Automatic Water Salinity Control System Using A Gravity TDS Sensor

Abstract

Water salinity is one of the water quality parameters that plays an important role in maintainng aquatic enviromental conditions. Instability in salinity levels can degrade water quality. Therefore, an automatic and continuous control system is required. This study aims to design and implement an Arduino-based automatic water salinity control system using a Gravity Total Dissolved Solid (TDS) sensor. The research methods include hardware and software design, sensor calibration, and system testing by comparing sensor measurements with reference values at several salinity variations expressed in ppm units. The preliminary data were analyzed using linear regression to determine the relationship between sensor reading and the reference values, as well as Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) to evaluate system accuracy. The test result show that the system was able to consistently track change in salinity, with stable readings at a 20% increase corresponding to 614.4 ppm and a 40% decrease corresponding to 296.0 ppm. These findings indicate that the Arduino-based automatic system combined with the Gravity TDS sensor has strong potential to be applied as an efficient solution for monitoring and controlling water salinity.