Mix the bell pepper, cucumber slices, red onion, cilantro, and lime juice in a medium bowl.
In a food processor add cilantro, sour cream, lime juice, olive oil, cucumber, garlic, coriander, and black pepper. Process until it is the consistency of a thick sauce. If too thin, add more sour cream. Add salt and pepper according to taste.
For the seasoning, combine the ground coriander, garlic powder, salt, and pepper, then season both sides of fillets.
Heat olive oil on medium high in a skillet and cook 1-2 minutes per side. Transfer to a plate or bowl before breaking into pieces.
Wrap tortillas in a damp paper towel and warm in microwave.
Top each tortilla with fish, fresh ingredients, cucumber cilantro sauce, and garnish with lime wedges.