Recently was able to do this with flounder but for the first couple of times did it with store bought talapia and it was great. So freshly caught fish is not a necessity but it does work great.
Ingredients-
2 fillets
2 bell peppers
2 tomatoes
1/2 chili pepper or jalapeno pepper
~ 2 tablespoons parsley
5-10 (or more) lemons or limes
Instructions-
Cut the filets into cubes about 1/2 inch long. Once the meat is cubed put it in a bowl with no seasonings. Fill the bowl with lemon/lime juice with cubes still inside, make sure it covers the cubes. Place the bowl in a refrigerator for about 1 hour and 30 mins. While the fish is sitting in the fridge, cut your bell peppers and tomatoes into small cubes as well. Then, cut the chili/jalapeno pepper in half and then cut one half into very fine small cubes. This will make the salsa mildly spicy but if you dont like spicy just don’t do the pepper or if you live very spicy ad a whole pepper. Do the same with the parsley (only a tiny bit). Once you are done cutting it all up, mix it together well in a bowl. Once the fish is done (normally takes about 1 hour and 30 mins) it will look VERY white compared to its normal pinkish state. If it still looks pink then let it sit for a while longer. Once it is ready mix it in the vegetables you cut and mixed. Mix it all very good and the salsa is ready. (many similar recipes online if you need a video)