const byte lowerlevel = 8;
const byte upperlevel = 7;
const byte pump = 9;
const byte UVLIGHTS = 10;

void setup ()
  {
  Serial.begin (9600);
  pinMode (lowerlevel, INPUT_PULLUP);
  pinMode (upperlevel, INPUT_PULLUP);
  pinMode (pump, OUTPUT);
  pinMode (UVLIGHTS, OUTPUT);
  }  // end of setup

void loop ()
  {
  while (digitalRead (lowerlevel) == LOW || digitalRead (upperlevel) == LOW)
     {
       Serial.println ("Water level LOW.");
     digitalWrite (pump, LOW);
     digitalWrite (UVLIGHTS, LOW);
     delay (1000);
     }
         
 while (digitalRead (lowerlevel) == HIGH || digitalRead (upperlevel) == HIGH)
     {
       Serial.println ("Water level NORMAL.");
     digitalWrite (pump, HIGH);
     digitalWrite (UVLIGHTS, HIGH);
     delay (1000);
     }
 
  
    }
  // other code here ...
   
   // end of loop