Fuzzy Logic-Based Control System to Maintain pH in Aquaponic

One of the important things in an aquaponic system is to keep the pH value of the water stable, so a system is needed to maintain the stability of the pH value. This paper describes the design of a pH control system in an aquaponic system based on fuzzy logic control. The system was developed using 2 pH sensors, a pH A sensor placed in the aquarium and a pH B sensor placed in hydroponics. The system also used 2 motor pumps, the first pump aimed to increase the pH value (pH up), and the second pump aimed to lower the pH value (pH down). In order to set the addition or reduction of pH to be more stable, a fuzzy logic algorithm was implemented to control the length of time the pump motor works. Testing the response system of the acid water to reach the set point took 11 seconds, the delay time t
d
was 4 seconds, the rise time t
r
was 3 seconds. However, in alkaline water, it reached the set-point for 11 seconds, the delay time t
d
was 3 seconds, the rise time t
r
was 2 seconds, and both occurred without overshoot.