If there is an odor after opening or using the tumbler:
- Pour boiling water with vinegar, citric acid, or baking soda into the tumbler and let it cool completely.
- Rinse thoroughly and check if the odor is gone.
Note: Do not soak the entire tumbler in the solution, as vinegar or citric acid may cause discoloration of the exterior.
There is no specific concentration, a guideline is 1 teaspoon per 200 ml of hot water.
To remove rust inside the tumbler:
- Pour boiling water with vinegar or citric acid into the tumbler and let it cool completely.
- Rinse thoroughly and wash the tumbler with dish soap.
Note: Do not soak the entire tumbler in the solution, as vinegar or citric acid may cause discoloration of the exterior.
There is no specific concentration, a guideline is 1 teaspoon per 200 ml of hot water.
To remove stains (like tea stains) inside the tumbler:
- Fill the tumbler with hot or warm water, and add a heaping teaspoon of baking soda or oxygen bleach. (Be cautious, as oxygen bleach may cause spills.)
- Let it sit until the water cools completely.
- Discard the solution, then rinse thoroughly.
- Wash with dish soap, rinse again, and dry.
Note: Do not close the lid during soaking or cleaning, as the increase in air pressure could be dangerous.