Once cooked, rinse the pasta and with cold water to stop the cooking process. Set aside.
Chop the apple, red onion, hard-boiled egg, and fresh dill. Transfer the chopped eggs and veggies into a large salad bowl. Add tuna, sweet relish, mayonnaise, and mustard to the large salad bowl. Combine everything well.
Add the pasta to the tuna salad mix. Season to taste with salt and pepper.