Descale the fish under water, using the back edge of the knife. Then, with a sharp knife, slit down the back of the fish and carefully remove the fillets! No bones allowed!! Squeeze the juice from the limes. Slice the onion and then dice it. Blanch the tomatoes in boiling water - cool and then peel off the skin and remove the pips. Measure the tomato juice and oil. Wash, dry and finely chop the cilantro. Smash the clove of garlic. Carefully remove the pips from the pepper. Place the fillets of fish into a mincer and when minced pour the lime juice over it and season with salt and pepper- set aside in a large bowl and refrigerate for up to 2 hours or until opaque. Before serving, toss with the remainder of the ingredients and serve immediately.