Cook the pasta based on the package instructions to al dente. Drain and rinse with cool water. Then place in a large mixing bowl.
In a separate bowl, whisk together mayonnaise, sweet pickle relish, lemon juice, salt and pepper. Then stir in the chopped tuna.
Gently stir in the celery, onion, hard boiled eggs and peas into the large bowl with the pasta.
Pour the mayonnaise mixture over the pasta mixture and stir until all the ingredients are well coated with the dressing.
Cover and refrigerate for at least 1 hour and then serve cold.
