Prep Notes: May prep one day before and let soak up to 12 hours or 20 minutes minimum to get fish fully cooked.
Juice the lemons, limes, orange, and grapefruit into a non-reactive bowl (glass or stainless steel). Add the shrimp and salmon into the juices and stir, make sure the fish is fully covered in juice as to allow it all to cook fully. Cover and place in refrigerator and cook for a minimum time of 20 minutes, maximum time 12 hours. It is fully done when the shrimp have turned opaque and pink, and the salmon is opaque and a lighter shade of pink. Add in garlic, jalepeno, onion, cilantro and tomato, just before serving. Once ready to eat, drain juices from bowl and serve with half of a sliced avocado. Salt and pepper to taste. Store remainder in refrigerator and eat within 48 hours.