<![CDATA[Dependence on handheld instruments in managing hydroponic melon cultivation at Tanjung Farm is a major constraint, as it is unable to detect changes in water conditions rapidly and continuously, thereby increasing the risk of crop failure due to delayed intervention. This study aims to develop an IoT (Internet of Things)-based nutrient solution quality monitoring system capable of measuring four water parameters in real-time, namely pH (potential of Hydrogen), TDS (Total Dissolved Solids), turbidity, and temperature, equipped with an automatic Early Warning System (EWS). The study adopted a Mixed Methods design with a prototype development approach conducted at Tanjung Farm during 2025–2026, involving 2 respondents consisting of the farm supervisor and farm manager as system end-users. The system was constructed using an ESP32 microcontroller as the central processing unit, four water quality sensor modules, a MySQL database for data archiving, and a web interface developed using the Laravel framework. Performance evaluation revealed that the pH sensor and DS18B20 temperature sensor achieved high precision with a 0% error rate compared to handheld measuring instruments, while the TDS sensor produced a 26.7% error attributed to the absence of a hardware temperature compensation module. Average data transmission latency from the microcontroller to the server was recorded at 5 seconds with EWS notification updates every 30 seconds. The resulting system successfully shifted conventional monitoring patterns toward an integrated digital solution operable remotely to maintain the productivity stability of hydroponic melon cultivation.]]>
