This is a recipe I found while searching for Pacific Island Recipes for ZWT. This is almost exactly the same as the one my Mother made, but she didn't add the carrot. This was found at AlohaWorld.com under Island favorites.
Follow the directions for cooking the macaroni on the package. Drain pasta and rinse with cold water.
While the pasta is cooking, cut up the onions, celery and carrot.
In a large bowl, add pasta, tuna and vegetables and add one cup of mayonnaise, adding more if needed. Season the salad with salt and pepper to taste. Cover bowl and place in the refrigerator until completely chilled. The longer it is refrigerated the more the flavors will marry.