AQUA GROW SMART INDOOR FARMING SYSTEM

Abstract

Growing fresh vegetables in cities is becoming harder because of limited land, irregular weather, rising water costs, and long supply chains that reduce freshness. Indoor farming using hydroponics allows plants to be grown without soil in a controlled environment, but it requires careful and continuous management of nutrient solution, water level, light, temperature, and humidity. This paper presents Aqua Grow, a Smart Indoor Farming System that uses Internet of Things technology to automate and monitor these conditions so that home users, schools, and small growers can maintain healthy crops with little manual effort. The proposed system is based on an ESP32 microcontroller connected to sensors for nutrient solution pH, electrical conductivity, water temperature, water level, air temperature, humidity, and light intensity. Actuators include a submersible pump for circulating nutrient solution, peristaltic dosing pumps for pH and nutrient adjustment, full-spectrum LED grow lights, an exhaust fan, and a mist humidifier. The controller reads sensors at regular intervals and adjusts actuators according to target ranges that depend on the crop and its growth stage. All electronics run from a single low-voltage supply, and the mains-powered loads are isolated through relay modules for safety. Aqua Grow uses closed-loop control to keep each parameter within its target range. When the pH of the nutrient solution drifts, small doses of pH-up or pH-down solution are added and the reading is checked again after mixing. When conductivity falls as plants absorb nutrients, concentrated nutrient solution is added in measured quantities. Lights follow a programmed photoperiod and their intensity is supplemented according to ambient light, while the fan and humidifier maintain suitable air conditions. A small camera captures images of the plants periodically for visual growth tracking. All sensor data and actuator events are sent to a cloud platform using MQTT over WiFi. A mobile application and web dashboard show live conditions, historical graphs, and plant images, and allow the user to select crop profiles, change targets, or switch devices manually. Notifications are sent when the reservoir level is low, when dosing solutions need refilling, or when any parameter stays outside its range. This gives the user remote visibility and control of the farm from anywhere. A prototype with lettuce, spinach, and basil grown in a nutrient film setup showed stable pH and conductivity over several weeks with far less manual checking than a manually managed setup, and water use was significantly lower than soil-based cultivation. Aqua Grow shows that affordable IoT hardware can make indoor hydroponic farming practical for urban households and small enterprises. Future work includes image-based detection of nutrient deficiency and disease, energy optimisation using solar power, and support for multiple racks managed from one application.