Fish with Curried Cucumber Tomato Water and Tomato Herb Salad

1 ( 1/2-lb) cucumber , peeled and chopped (1 1/2 cups)

1 ( 1/4-lb) tomato , chopped ( 3/4 cup)

1/4 teaspoon curry powder (preferably Madras)

1/4 teaspoon salt For tomato herb salad

1 lemon

1 lb assorted small heirloom tomato es, halved (larger ones quartered)

1/4 cup loosely packed fresh parsley leaves

2 tablespoons thinly sliced fresh basil

2 teaspoons finely chopped fresh chives

1 teaspoon finely chopped fresh lemon balm

1/4 teaspoon black pepper

1/4 to 1/2 teaspoon sugar (to taste)

1/4 teaspoon salt For fish

6 (5- to 7-oz) mild white-fleshed fish fillets such as flounder, sea bass, or snapper

1 tablespoon extra-virgin olive oil