Control of Electrical Conductivity for NFT Hydroponic Systems using Fuzzy Logic and Android Environment

Abstract

Nutrient Film Technique (NFT) is a method of hydroponic systems that utilizes circulating water containing nutrients as a medium for plant growth. One important parameter in NFT that can affect plant growth is the density of the nutrient solution based on the level of conductivity. Conductivity of the solution is expressed by Electrical Conductivity (EC) which is a measure of the amount of salt dissolved in the solution. Control of EC parameters is intended to maintain EC values in ideal conditions depending on the type of plant. In this study, we applied fuzzy logic methods to control the condition of EC values in NFT hydroponic plants. By using an Android-based application connected to the internet, we can control and monitor all parameters remotely. The experiment was conducted on a proportional small scale cultivation model consisting of two reservoirs (ABmix and water) and one mixing tank with pump flow that can be adjusted using fuzzy logic. EC parameter values are maintained in the ideal range according to the setpoint input provided. The ideal EC parameter values on the plants tested are 1.0 mS/cm to 1.5 mS/cm. The system takes around 101 seconds to restore the lowest EC value to be ideal and around 89 seconds to restore the highest EC value to an ideal condition.