Design of a Water Quality Monitoring System Utilizing IOT Platform for Hydroponics Application

Abstract

Hydroponics is a farming method that grows plants in nutrient solution. However, hydroponics requires a lot of manpower to monitor parameters such as pH, temperature and dissolved oxygen. The digitalization and automation have driven the concept of Industrial Revolution 4.0, which enables automatic collection of data. The data acquisition is developed based on this concept is able to monitor the environmental or physical situation remotely and continuously. Thus, this project was carried out to design a smart water quality monitoring system utilizing IoT platform for hydroponics application. A waterproof temperature sensor (DFRobot (DS18B20s), ±0.13 oC), dissolved oxygen sensor (DFRobot (SEN0237-A), ±0.13) and pH sensor (GI Electronic (E-201-C), ±0.04) were selected to collect the real-time data of the nutrient solutions while an Arduino and Raspberry Pi were used for data processing. Node-RED was used to make real-time and historical viewer program in order to monitor and analyse the parameter remotely. By combining the sensors with Arduino and Raspberry Pi, the hydroponics system can be monitored remotely. Lastly, the water monitoring system was implemented in the hydroponics for 28 days. During the cultivation period, it was observed that the dissolved oxygen concentration and water temperature were generally constant at 6 ppm and 23 oC respectively while the pH of the nutrient solution were reduced from pH 6 to pH 3 during the cultivation. Results suggested that a robust water quality monitoring system was successfully designed, and the sensors are stable for continuous data collection at a 5 seconds sampling rate throughout 28 days for hydroponics application.