You can buy a pack of 5 Scrubbing Bubbles drop-in tablets from Amazon for $5.48. Best For Hard Water Stains: Iron Out Automatic Toilet Bowl Cleaner If you live in an area with hard water ...

To eliminate rust stains, you'll want a highly acidic toilet cleaner, which can eat away at the alkaline chemical makeup of rust. We recommend using citric acid or Zep's Acidic Toilet Bowl Cleaner ...