Boil the potatoes whole in the skin until fork tender, about 20-30 minutes. Run water over the potatoes to cool. Peel & chop the potatoes. In a large bowl, combine the potatoes, eggs, onion, dill pickles, mayo, & mustard. Pour in the dill pickle juice & stir to combine. Season to taste with salt & pepper. Sprinkle with paprika, if desired. Refrigerate until serving.