Cut the tilapia fillets into small cubes.

Bring water to a boil with salt, 1 clove of garlic, and 1/4 of the red onion.

Cook the fish in the boiling water for 10 minutes.

Drain the fish and place it in a bowl.

Add the lime juice and let it sit for 10 minutes.

Finely chop 1/2 red onion, the cilantro, and the tomatoes.

Add the chopped vegetables to the fish and mix well.