Fill fryer with vegetable oil to its maximum level, or fill a deep pot no more than halfway with the oil. Preheat fryer to 350 degrees F.
Fill a gallon resealable plastic bag with 3 cups wheat cereal. Using a rolling pin, lightly crush cereal into small crumbs. Set aside.
In a shallow bowl, combine flour, ranch dressing mix, and salt. Coat fish with seasoned flour mixture then shake off excess flour. Dip in eggs and roll in crushed cereal. Continue with remaining fillets. Carefully add 3 to 4 pieces in fryer and cook until golden brown and crisp. Repeat with remaining fillets.
Serve with tartar sauce and seasoned chips.
In a small dish, strain relish and discard juices. In a separate bowl, combine strained relish with mayonnaise, mustard, and lemon juice. Stir thoroughly. Add salt and pepper to taste. Serve with fried halibut.