Design of pH Control System and Water Recirculation in Aquaponic Cultivation Using Mamdani Fuzzy Logic Control

Aquaponic cultivation is an integration between hydroponic plant cultivation and fish cultivation (aquaculture) in such a way that an organic symbiosis is formed. Aquaponic cultivation requires the pH of the water to be maintained at a value between 6.3 to 7.3 to prevent membrane damage to plant roots. The same water is also used for the fish's living environment. The cloudier the water, the greater the ammonia content, so water recirculation is necessary. In this research, the Mamdani fuzzy logic method is implemented in a dynamic pH and water turbidity control system within a certain time span through a relay pump for acid and base solutions as well as speed and circulation pumps and water filtration. The IoT technology on the ESP8266 is used to control and monitor sensor data parameters used in aquaponic cultivation. From the results of testing the pH control action, the fastest time is 7.27 seconds to reach the ideal value of the initial alkaline pH condition with the average time needed to reach the set value is 11.10 seconds. While the longest time is 24.68 seconds when the initial pH is acidic towards the ideal with the average time required to reach the set value is 21.41 seconds. The turbidity quality of the recirculating system water before filtration was 8.11% and after filtration decreased to 0.46%.