Gather all your ingredients so everything is ready to go.
Place the shrimp in a bowl. You can chop them into smaller pieces or leave them whole, depending on your preference. Pour the lemon juice over the shrimp, making sure they are fully covered. Cover and refrigerate for about 30 minutes, until the shrimp turn opaque and slightly firm.
Add the chopped onions, tomato, cucumber, radishes, and minced garlic to the bowl. Toss gently to combine.
Gradually add the minced jalapeño and chopped cilantro. Taste as you go so you can adjust the heat to your liking.
Pour in the tomato and clam juice cocktail a little at a time until you reach your preferred consistency.
Cover the bowl and refrigerate for another 1 hour so the flavors come together.