If citric acid doesn’t work, bring out the big gun: white vinegar. Pour half a cup into the bowl, add a few tablespoons of baking soda, and watch it fizz like a science fair volcano. Warning: The fizz is violent for about five seconds, then it’s sad. That’s normal. Let the mixture sit for an hour, then scrub again.
Pro tip: Never mix vinegar with bleach unless you want to create toxic chlorine gas. Unless you’re a supervillain, skip that. Stick to one cleaner at a time.
