Spicy, zingy fermented cukes deliver plenty of probiotics. The double-sealed water bag helps keep them submerged so they ferment thoroughly.
Toss together cucumbers and salt in a medium bowl. Place cucumbers in a colander; let stand 20 minutes. Rinse and drain well.
Combine oil, basil, gochujang, ginger, garlic, sugar, and fish sauce in a bowl. Add cucumbers; toss to coat.
Place cucumber mixture in a mason jar. Press down cucumbers firmly, leaving 4 inches of headspace. Place 1 cup water in a small ziplock plastic bag; seal bag. Place inside a second ziplock bag, and seal. Place bags on cucumbers; seal lid. Let stand at room temperature 7 days, opening and resealing lid once per day. Discard water bags before serving.