Water Quality Monitoring for Sustainable Smart Aquaponics System

Water quality in aquaponics is a very important factor for sustainable farming. It relies on many parameters, some of which includes water temperature, pH, ammonia and dissolved oxygen levels. Changes in water quality parameters can have huge impact on the growth of plant and fish in the system, as it affects manpower costs, hence productivity. This paper introduces a water quality monitoring system for smart aquaponics in a research setting. It discusses the overall hardware and software solution via Internet-of-Things (IoT) and shows the impact on the growth rate of fish and plant. The aquaponics uses solar panel as a source for energy. Users can monitor water quality parameters via mobile application on the smartphone. ESP32 acts as the main processor, while dedicated sensors measure water quality parameters (water temperature, pH and dissolved oxygen levels). The output is transferred to Blynk application database via cloud server for analysis purpose. The dissolved oxygen level is controlled through a feedback switching mechanism, which turns on the air pump should the dissolved oxygen level goes below optimum, notable after midnight until dawn. In effect fish survival improves and sustainable growth of mustard plant are achieved. Initial tests over a 3-week period shows promising use of IoT for water quality monitoring in aquaponics.