Combine the 1/4 cup of lime juice with the cilantro and olive oil in a large, shallow dish and mix well. Place the filets in the marinade and flip them, making sure to coat every surface of the filet. Leave the fish in the marinade and place it in the refrigerator for 30 minutes,turning once. Fire up the grill to medium-high heat (around 350-400 degrees). Charcoal recommended.