Dry the fish filets, sprinkle with salt and pepper, then lightly flour. Combine the horseradish and bread crumbs. Lightly beat the eggs and add water. Dip only one side of the filets first in the egg and then the bread crumb mixture. Fry first on the breaded side until golden, turn and fry slowly on the other side until cooked and firm. In blender combine 1/4 c oil and chives. Lightly fry the leek in oil, dry on a paper towel. Boil the potatoes until tender. Drain and place on a cookie sheet in the oven at 375F until slightly dry. (10 to 15 Min) Mash the potatoes adding butter as needed until creamy. Season to taste with salt and pepper. Place a serving of mashed potato on a plate. Place the cooked filet on top. Surround with chive oil. Place leek on top as garnish.