Place water, lemons, salt and crab/shrimp boil (bags and liquid concentrate) in a large pot and bring to a rolling boil. Add potatoes and corn, resume boil and cook for 5 minutes. I used small potatoes (1 1/2 – 2 inches in diameter). If you prefer to use larger potatoes, they would require additional cooking time and should be added before corn. Add sausage and shrimp. Bring to a boil, cover and remove from heat for 10 minutes.