Cut the fish fillets into thin, even strips.
In a bowl, whisk together lemon juice, olive oil, fresh dill, minced garlic, sea salt, black pepper, lemon zest, onion powder, and cayenne pepper.
Place fish strips in a large zip-lock bag and pour in the marinade. Ensure all pieces are coated. Marinate in the refrigerator for at least 2 hours.
Preheat your dehydrator or oven to 145°F (63°C).
Arrange the marinated fish strips on dehydrator trays or oven racks lined with parchment paper.
Dehydrate or bake for 4-6 hours, or until the jerky is dry and slightly pliable.
Allow the jerky to cool before storing in an airtight container.