Design and Construction of an ESP32-Based PPM Sensor in a Hydroponic System

Abstract

Hydroponics is a soil-less cultivation method that requires nutrient control. strict monitoring, especially the EC or PPM levels as indicators of solution quality. Manual use of TDS meters often results in inaccuracies, limited data historical, and does not allow for periodic monitoring. Literature review shows that implementation of the Internet of Things (IoT) through the ESP32 microcontroller equipped with Wi-Fi and Conductivity-based PPM sensor that has been calibrated using standard solution 1413 µS/cm and 2.76 mS/cm are able to improve measurement accuracy and monitoring stability. Through the Systematic Literature Review approach, it was found that the integration of PPM sensors, ESP32, and the MQTT protocol can provide real-time nutritional data, sending threshold notifications, as well as facilitating remote monitoring. The novelty of this study lies in the implementation of a low-cost monitoring system with real-time features. adapted for small-scale farming groups.