Heat grill pan over medium high heat or preheat outdoor grill.
Combine the juice and zest of 2 lemons, oregano, parsley, 2 cloves garlic, olive oil and add fish, turn to coat and season with salt and pepper.
Wrap tortillas in foil and place in warm oven or directly on grill to soften and warm through.
Shred romaine lettuce and combine with sliced onions.
Slice hot peppers and reserve.
Combine red peppers and yogurt in food processor. Add cumin, 1 clove garlic, zest and juice of remaining1 lemon, cucumber and process until smooth, transfer to a bowl.
Grill fish 6 to 7 minutes until firm and cooked through then cut into cubes.
Serve fish to wrap in soft tortillas with lettuce, onions, hot peppers and sauce.