視頻裏小高姐用的是soda ash。see inside about the difference between two.

Soda ash and washing soda are chemically the same thing (sodium carbonate), but washing soda is heavier and clumpier because it contains significantly more moisture.

Hazards Associated with Sodium Carbonate

Eye contact can cause permanent corneal injury and possible burns. If you use sodium carbonate or soda ash in the household, take care to avoid ingestion or inhalation of dust. Due to these potential hazards, sodium carbonate should be handled with care.