Boil water in a large pot and add a pinch of salt.

Add the elbow macaroni and cook according to package instructions until al dente.

Drain the macaroni and rinse under cold water to stop the cooking process.

In a large mixing bowl, combine the mayonnaise, apple cider vinegar, salt, and pepper.

Add the cooled macaroni to the bowl and mix well to coat.

Incorporate the diced celery, red bell pepper, and carrots into the mixture.

Stir in the chopped green onions and sweet pickle relish.

If using, gently fold in the canned tuna for added protein.

Adjust seasoning to taste with additional salt and pepper.

Cover the salad and refrigerate for at least 1 hour before serving to meld the flavors.