Combine paprika, onion powder, salt, black pepper, cayenne pepper, oregano, and garlic powder in a bowl. Rub about 1 tablespoon of the mixture on each side of both tilapia fillets, making sure to use up all the seasoning. Let fillets sit while preparing the quinoa, about 15 minutes.
Combine water, quinoa, and salt in a medium saucepan. Bring to a boil; cover and reduce heat to low. Cook until quinoa absorbs all the liquid, 12 to 15 minutes. Remove from heat. Stir in lime zest, juice, and cilantro. Season with salt.
Heat oil in a pan over medium-high heat. Cook tilapia fillets until fish flakes easily with a fork, 2 to 3 minutes per side.
Arrange romaine lettuce and spinach over 2 bowls. Divide tilapia, cooked quinoa, black beans, and tomato over the bowls. Top with avocado and pepitas. Serve each portion with a lime wedge.