Rinse cucumbers, onion, and bell pepper under cool water. Slice cucumbers thinly and cut bell peppers into thin strips, discarding the seeds. Cut red onion into thin rings. Place vegetables in a large mixing bowl.

In a separate bowl, whisk together vinegar, water, sugar, salt, black pepper, and garlic powder until sugar and salt dissolve.

Pour the pickling solution over the sliced vegetables and gently toss to coat evenly.

Cover the bowl with plastic wrap or transfer to a sealed container and marinate at room temperature for at least 10 minutes.

Stir the salad again before serving. Enjoy it cold or at room temperature.

Store any leftovers in an airtight container in the refrigerator for up to one week.