float tempSensorPin = A0; //Define the temp sensor pin 
int heaterPin = 2; //Define the heater pin number
int thresholdTemp = 22; //Define the threshold temp

float pHSensorPin = A1; //Define the pH sensor pin
int filterSystem = 3; //Define the filter system pin number
int thresholdpH = 7; //Define the threshold pH

float ammoniaSensorPin = A2; //Define the ammonia sensor pin
int waterPump = 4; //Define the water pump system pin number
int thresholdAmmonia = 0.5; //Define the threshold ammonia level

#include <LiquidCrystal.h> //Connecting the LCD Display 

LiquidCrystal lcd(12, 11, 10, 9, 8, 7); //Pin numbers for the LCD Display
float temp = 0;
void setup() {
  
Serial.begin(9600); //Initialising the serial communication 

pinMode(heaterPin, OUTPUT); //Set the heater pin as an output
pinMode(filterSystem, OUTPUT); //Set the filter system as an output 
pinMode(waterPump, OUTPUT); //Set the water pump as an output 

lcd.begin(16, 2); //Defining the type of LCD Display in use 

}

void loop() {
 
int temp = analogRead(A0); //Read the temp from the sensor
float celsius = (5*temp*100)/1024; //Sensor value converstion to C

Serial.print("Temperature: "); //Print the temperature term 
Serial.print(celsius); //Print the value 
Serial.println("C"); //Print the unit 

//Check if temperature is above the threshold value 
  if (temp < 22) { //if temperature is lower than 22 degrees
    digitalWrite(heaterPin, HIGH); //turn on heater system
  } else if (temp > 25) { //if temperature is higher than 25 degrees
    digitalWrite(heaterPin, LOW); //turn on heater system
  } else { //if temperature is within the desired range
    digitalWrite(heaterPin, LOW); //turn off heater system
 
  }

delay(500); //Wait for 500ms

int pH = analogRead(A1); //Read the pH from the sensor 
float pHLevel = (14*pH) / 1024; //Sensor value conversion to pH level 

Serial.print("pH Level: "); //Print the pH level term 
Serial.print(pH); //Print the value 
Serial.println(" pH"); //Print the unit 

//Check if pH level is above the threshold value
if (pH>thresholdpH){
  digitalWrite(filterSystem, HIGH); //Turn on the filter 
} else{
  digitalWrite(filterSystem, LOW); //Turn off the filter 

}
delay(500);//Wait 500ms


int ammonia = analogRead(A2); //Read the ammonia level from the sensor
float ppm = (ammonia*5) /1024; //Sensor value conversion to ppm 

Serial.print("Ammonia: "); //Print the ammonia term
Serial.print(ppm); //Print the value 
Serial.println("ppm"); //Print the unit 

//Check if Ammonia level is above the threshold value 

if (ppm>thresholdAmmonia){
  digitalWrite(waterPump, HIGH); //Turn water pump on 
} else{
  digitalWrite(waterPump, LOW); //Turn water pump off

}
delay(500); //Wait 500ms

  // Clear the LCD
  lcd.clear();
  
  // Display temperature reading
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(celsius);
  lcd.print("*C");
  
  // Display pH reading
  lcd.setCursor(0, 1);
  lcd.print("pH:");
  lcd.print(pH);
  
  // Display ammonia reading
  lcd.setCursor(6, 1);
  lcd.print("NH3:");
  lcd.print(ammonia);
  lcd.print("ppm");
}