Preheat your oven to 375°F (190°C).
Cook egg noodles according to package directions; drain and set aside.
In a large mixing bowl, combine tuna, salmon, peas, cheddar cheese, milk, cream of mushroom soup, garlic powder, salt, and pepper.
Add cooked noodles to the mixture and stir until evenly coated.
Transfer the mixture to a greased 9x13-inch baking dish.
Sprinkle crushed potato chips on top, if using.
Bake uncovered for 25-30 minutes, or until the top is golden and bubbly.
Let it cool slightly before serving.